ID: PH01_AUX / Elaine Barker

TitleAuxiliary Units in WW2
AbstractDuring World War Two, with the fall of France to the Nazis on 22nd June 1940, a German invasion of Britain was expected daily and the East coast was deemed to be particularly vulnerable.

The German plan for the invasion of Great Britain was code-named Operation Sea Lion. With the expectation that the German Air Force was going to destroy the RAF, the Germans requisitioned every useable river barge in France, Belgium and Holland. These were assembled to provide transport across the Channel for 260,000 German troops. The invasion fleet was made up of 168 transports, 1,697 barges, 360 tugs. Hundreds of these were collected from internal waterways, then taken to shipyards. Ramps [were] fitted to bows to enable tanks and guns to be disembarked ... All this shipping was collected in German North Sea ports at first; then a fortnight or so before D-Day were to be transferred to invasion ports ... Landings [were to be] on a short front of about 50 miles between Folkestone and Beachy Head. Four main landings [were planned including] one at Brighton. Four thousand air-borne troops [were] also to be dropped. R J Thompson The Invasion That Didn't Come Off from King Cole's Essex.

Plans for all day-to-day running of our country were drawn up by the German government and it was intended to intern every man between 17 and 45 while camps were set up in France to receive them. Lists were made of British Jews, freemasons, refugees, known socialists and communists and all 'liberals' including every MP. They were to be either, taken into custody and interrogated, or be put under house arrest. All the clergy were to be under house arrest. German intelligence had collected photographs from the air of our coastline and the land 10 miles behind it. In preparation for invasion, Ordnance Survey maps were overprinted with information as to the whereabouts of every military establishment, harbour and shipyard. The AA Handbook of 1937 was also over-printed indicating important buildings in all the major towns.

It was in this climate the race to set up a British 'resistance' began. As Lord Ironside, the son of the Commander-in-Chief of the Home Forces was to write later

The role was to observe and hinder every action of the supposed German occupation force

Resistance groups, which were to be known as 'Auxiliary Units', were quickly set up, their aim to create havoc with the enemy's supplies and communications through sabotage. Their hideouts were referred to as 'OBs' or Operational Bases.

In the summer of 1940, Commander-in-Chief of GHQ Home Forces, Field-Marshall Ironside, directed Colonel Gubbins, an expert in guerrilla warfare, to set up a small group of officers to recruit civilians as Auxiliers in the areas most at risk. He offered him any men or supplies needed and, in fact, the Auxiliary Units were the best armed of all the forces, also being the first to receive newly developed weapons.

In Essex and South Suffolk, the recruiting officer was Noel Andrew Croft. Having been a member of an Independent Company stationed in Norway, (forerunners of the British commandos), in the summer of 1940, he had just returned home following the failed attempt by the allies to free Norway from Nazi occupation. He was well-trained in sabotage and, later was to work with the French resistance behind enemy lines. It was he who was asked by Colonel Gubbins to set up the first of the Essex and Suffolk Auxiliary Units. These units were to be set up within 30 miles of the most vulnerable coasts. As the Eastern Regional Commissioner was to say in a statement

When invasion does take place it is practically certain there will be a heavy attack in the Eastern Counties Essex At War, Essex County Standard

Andrew Croft was to choose men from the Home Guard and, in his own words, train them in guerrilla warfare and help them construct hide-outs for up to eight men, usually underground ... I chose patrol leaders from successful farmers and fruit growers, one a Master of Foxhounds, another a game warden. A Talent for Adventure, Andrew Croft

These patrol leaders would then nominate suitable men, usually known to them, who underwent a thorough vetting arranged by Croft before being recruited. Selected for their skills and experience, there were men who had fought in WW1, and men who worked on the land; familiar with firearms, a thorough knowledge of the area and an ability to live off the land. They had to master basic military training with explosives, firearms, map-reading and subsistence.

Each patrol as it was called was about seven to ten men in size, members of the Home Guard. These men were marvellous. Gamekeepers, smugglers, poachers, all that. Grand people. Tough. A very awful job if the Germans had landed, to stay behind and sabotage their communications, but that was the aim and object ... I think they would have been quite a problem for the Germans to compete with and I think they would have been effective. But of course they couldn't have had a profound effect, just a nuisance effect. Andrew Croft, Imperial War Museum Sound Archive

Training was intensive, almost every night during those first three months. It was largely local, although some leaders went on courses at Coleshill, Wiltshire, which became the Headquarters for the Auxiliary Units. Later, River House at Earls Colne became the headquarters and training centre for Essex.

The first hide-outs were fairly rudimentary, shallow and cramped 'dens', but as time went on a standard design was used, referred to as an 'elephant shelter'. It was constructed from curved corrugated iron sheets to form a semi-circular tunnel a minimum of 20 foot long and over 10 foot wide with two entrances, one at least 30 yards away along a tunnel of 30 inch concrete pipes.

The ingenious trapdoors were impossible to find unless you knew where they were. Equally ingenious was how the Auxiliers managed to dig the shelters, remove very large quantities of earth and reinstate the area to look as it did before without attracting attention, although the Royal Engineers were called in to install some of these shelters. The shelters were then stocked with explosives, weapons and essentials including food and water; supplies that would last up to fourteen days.

In the Imperial War Museum Sound Archive, Andrew Croft described how these underground shelters were stocked.

Stiff with *sticky bombs and grenades, phosphorous grenades as well, Bren guns and Stens and ammunition galore and fully stocked with food of the non-perishable variety.

*a sticky bomb was a glass flask filled with nitro-glycerine and coated with an adhesive allowing it to be glued to a passing vehicle.

Very early on, Croft writes, he stored weapons in his father's coachhouse at the vicarage in Kelvedon - his father was the Rector of Kelvedon Church!

The Operational Base reconstruction at Parham Resistance Museum based on the Auxiliary Unit of Stratford St Andrew, Suffolk.

By the autumn of 1940 Croft had set up 24 patrols, mainly in Essex but also up into Suffolk as far as Framlingham He was then to move on to work on developing landing craft for commando raids on the coast of Europe but work continued recruiting and training saboteurs round the coast of Britain.

By the end of 1941 there were 534 hidden Operational Bases in the UK with 138 more on the way. It is believed there were 3,500 men who attended training at Coleshill and overall 5,000 men ready to engage in guerrilla warfare at the point of invasion.

The Prime Minister, Winston Churchill, was fully aware of the Auxiliary Units' existence and received regular reports. It was he who demanded that all Auxiliers be issued with revolvers

The Auxiliers were generally older men or those in reserved occupations, those exempted from call-up, or too young to be called up, so the majority were in the Home Guard. Here in Essex, recruits were told they belonged to the 203rd Battalion of the Home Guard but in fact their names never appeared on any Home Guard list and their battalion 'didn't exist'. As a last resort if they were questioned too closely by local military or police their only option was to refer them to their Intelligence Officer (here in Essex, Croft, or his successor). Neither did they have any Prisoner of War rights afforded to regular uniformed soldiers. If captured, any local authorities would deny knowledge of them and with no protection from the Geneva Convention, as saboteurs, they risked being executed. Their life expectancy was judged to be between 12 and 14 days after invasion. Their families were unaware of their exact roles and they had no communication with other patrols, each Unit operating alone.

They were essentially intended as units to interfere with the original perimeter the Germans might make. There was no question, at least when I was there, or when Gubbins was there, of a nationwide guerrilla force, although I confess we had this vaguely at the back of our minds if we were granted time Capt. Peter Wilkinson *MI(R) and **SOE officer, London. Imperial War Museum Sound Archive

*Military Intelligence (Research)
** Special Operations Executive

Although the pictures taken of Auxiliary Units when they were being stood down show them in Home Guard Uniform, they in fact wore their normal work clothes when on exercise.

Upon the invasion, all Auxiliers were to 'disappear' to their Operational Base, observe the enemy and set to work straight away, sabotaging German communications by stealth at night. It was thought that in those first days of invasion the enemy would be at their most vulnerable. The railway system and airfields were expected to be principle targets as were military headquarters.

Another vital secret unit was the local wireless network operated by the Royal Corps of Signals with outstations near the coast. Using a system of civilian spies, scouts and runners and ingenious 'post-boxes', details of enemy activity could be communicated. The Auxiliary Units would also assess their targets for the night by observation during the day.

Chillingly, Auxiliers were expected to kill any wounded comrades if they were too ill to survive.

We know now there was a Unit (often called a 'Patrol') at Birch and Layer de la Haye with an Operational Base in Layer Woods and another one at Fingringhoe with a base at Ballast Quay. There was a Unit at Rowhedge although little is known about it.

Layer Auxiliary Unit

These three images courtesy of local historian, John Moore, show what remains of the Operational base used by the Birch and Layer Auxiliary Unit. It is situated on private land in Chest Wood, Layer de la Haye and the pictures were taken in 2007.

Chest Wood Bunker entrance 2007

Chest Wood interior of Operational Bunker 2007

Chest Wood overview of site of Operational Bunker

This description below was recorded by Fred Nash, the County Military Archaeologist at the time.

British Resistance Hideout, Chest Wood, Layer de la Haye

Ordnance Survey Map Reference TL 9635 2096


In early 1996, the remains of an underground British Resistance (or Auxiliary Unit) hideout were reported by Essex County Council officers at Chest Wood, Layer de la Haye. The structure had been cut into an ancient dyke, at its north end, and then recovered to lie hidden beneath the forest floor. By 1997, the top of the dyke had fallen into the main chamber of the hideout exposing the rotting arches of the corrugated steel roof. Visited in February 2007, the remains were re-discovered and documented for this record. It is typical of British resistance hideouts to be located in woodland, often quite far from habitation. It is also typical that they should be cut into a bank, in this case an ancient dyke, as this would be easier to construct than a deep hole in the flat ground. The top of the dyke has collapsed over a significant area here, probably into the entrance tunnel, the outer chamber and the main chamber. All hideouts are thought to have had an escape tunnel and the ground has probably fallen into this as well. However, a substantial part, perhaps 4 feet of the central width of the roofing now lies exposed and investigating the gap beneath this it is clear that much of the roofing is still intact. However, the survival of end walls, entrance, escape tunnel, etc is unknown. Around the site, bits of corrugated steel sheeting lie half-buried in the overgrown, broken-up ground. Along the west end of the dyke a small stream contributes to the difficulties in gaining the overall picture of the site.

Former Layer resident, Brian Chaplin, now resident in Australia remembers the hideout.

Re the WW2 camp I know it well we used to find all sorts of ordinance there and one boy picked up a hand grenade and removed the pin which killed him, I can't remember his name but it was something like Bleakly or peachy [Bleakley]. I remember taking home a few 2" mortar bombs to show my father who went ballistic and put them in a bucket of water, well he was Royal Army Medical Corps. Brian Chaplin by e mail

Below is the Below is the 'stand-down' picture of the Birch and Layer Auxiliary Unit

Members of the Birch/Layer-de-la-Haye Auxiliary Unit, part of the wartime British Resistance. What is notable is that the men wear their revolvers, not something issued to ordinary Home Guards. 
Back row, Robert Strathern, W.A. Abbott, Richard Golden (Dick) Fairhead 
Front row, George W Ward, Sgt David Macauley, Basil Rootkin 
Photograph taken at Dukes Farm, Layer Marney.
The photograph is from the Birch photograph collection at Mersea Museum, but the caption is from the British Resistance Archive website which has much more background - see

David Macauley was the sergeant of the Birch/Layer Unit and a dairy and general farmer at Beckingham Hall, Hardy's Green, Birch where his grandsons still farm. George W Ward, his Corporal, was a haulage contractor and in the 1939 register was living in Birch with W A Abbott who was a heating engineer. Robert Strathern was a farmer at Heath Farm, Birch. The Stratherns were among many Scottish farming families, who moved down from Ayrshire, in their case in 1929/30, to take up farms in Essex and Suffolk. They still farm in the area.

Robert Strathern's sons, Jimmy and Robin, remember their father telling how hard it was manning the bunker at all times when the risk of invasion was deemed to be particularly high. Robert also went away to Coleshill for training and was chosen to go on a raid to France but not being able to speak French, he didn't go.

The approach to the Layer bunker was always by foot and the trapdoor entrance was under a tree stump and operated mechanically, too heavy to be lifted otherwise. There was also a trip wire attached to a bell to alert the bunker's occupants to strangers.

Robin remembers how badly equipped the local Home Guard were with their wooden rifles. They were generally older men and he thinks there was a certain amount of jealousy aimed at the younger men of the Unit who were equipped with revolvers and automatic guns. He thinks the Home Guard had some inkling that the men of the Unit were involved with secret operations but the Unit was sworn to secrecy. Robin remembers his father's weapons were locked away under the stairs and Robert came and went with no explanation. Robin also remembers the Unit stealthily removing the wooden rifles of the Home Guard while they were training on the cricket field!

Another member of the unit, Basil Rootkin, was a lorry driver living near Hardy's Green, Birch. The name of another member of the Unit not in the picture above, Pte A W L Howe, appears on the Coleshill website but there are no further details.

Richard Golden 'Dick' Fairhead was from a local farming family having stayed at home to assist his father with the farm at The Rows in Layer de La Haye. It is known that Richard travelled to Coleshill for training. In 1999, Mrs Fairhead talked about how her late husband had remained quiet about his war service until the publication of the first book to investigate the existence of a British resistance, The Last Ditch by David Lampe in 1968.

Because Auxiliers had been top secret and were unable to prove their war-time work, they were not given the Defence medals which other home defence groups were awarded. This decision was challenged and Mary Fairhead was able to claim her husband's Defence Medal after his death in 1995.

WW2 Defence Medal

In August 2013 journalist Tom King interviewed Mary Fairhead about her late husband's involvement in the Auxiliary Unit in Layer de la Haye.

Tom wrote

Few Memories articles in recent years have generated such a lavish response from readers as the July 5 edition about Winston Churchill's Underground Army.

Formed in 1940, this top secret unit of volunteers was set up as a last-ditch resistance force in the event of a German invasion.

Nicknamed the 'stay-behinds', their do-or-die role was to emerge at night-time from hidden underground lairs, then in Churchill's words 'to harass enemy lines and slit enemy throats'.

Essex, a prime candidate for any choice of invasion route, was a key centre of stay-behind activity.

Even loved ones were unaware of the existence of this unit. Mary Fairhead, from Nayland had been married to her late husband Dick, a farmer, for 16 years before she learned anything about his cloak and dagger war-time activities.

'He was a farmer's son' she says. 'His brother had gone off to war, but he had to remain behind to look after the farm. This was his contribution to the war effort'

Dick was a member of a stay-behind unit based at at Birch. Mary says 'Their secret headquarters for want of a better word, was in a wood in Birch. You lifted up a tree stump and down you went into the bowels of the earth. Of course, this was in the middle of the night, when it was pitch dark. Dick said it was all a bit scary'

Because they did not officially exist, the stay-behinds were denied any sort of medal or other acknowledgement. It has taken 73 years for a proper tribute to be paid. This year, for the first time, surviving members have been invited to join the march past the Cenotaph on Remembrance Day.

It is too late for Dick Fairhead who died in 1994.

However, after what amounted almost to a military campaign in its own right, Mary managed to have a home defence medal presented to her on his behalf.

Stay-behind headquarters, like the one described by Mary, were constructed by the Royal Engineers. But individual members used to build coffin-like one-man underground shelters for themselves at strategic points round the Essex countryside. They were designed to provide instant hiding places.

Several readers recall childhood experiences of playing in these shelters. The hiding places might have been invisible to German patrols but no amount of skill could prevent small boys from uncovering them.

Paul Nice from Hockley says; 'My family had a smallholding adjacent to Beckney Woods in Hockley. We used to play in the woods when I was a kid in the Fifties, and there was one of these hiding places there. We used it as a den, although back then we never knew anything about its history, of course.'

Officially, the stay-behinds were just ordinary members of the Home Guard. Even fellow Home Guard members were unaware of their shadowy activities.

Mary Fairhead says 'My husband used to tell everyone that he had been a 'guardsman'. He was only 5ft 6ins in height so that always seemed a bit unlikely'.

Linda Jones, originally from Benfleet, now living in London, has sent Memories a rare picture of an Essex stay-behind unit based at Ashingdon. Nothing in their uniform distinguishes them from any other Home Guard unit. The man in the beret is their commanding officer, Jack Ford, who in more peaceful times had been headmaster of Ashingdon Secondary School.

The stay-behinds buried large caches of explosives for sabotage activities, and from time to time, these hordes would be dug up on building sites.

Dorian Kelly of Colchester, recalls an incident when workers were busy demolishing the town's old bus station.

He says 'the site manager noticed a man lingering close to the site, shifting uneasily from foot to foot. He went up to him to find out what was the matter.'

The stranger said 'Look, I'm not supposed to tell you this, because I've signed up to the Official Secrets Act. But where you're working, there's a large amount of unexploded ordnance, which I buried there during the war.'

Alongside the Home Guard photograph, Linda Jones has also sent a cutting - unfortunately undated - from our South Essex sister paper, the Echo.

It relates to the discovery of another arms cache, near St Andrews Hospital, Billericay. Readers may be struck by the name of the original source.

It reads 'Police are checking out a report of a huge store of war-time guns and ammunition ... they appealed in yesterday's Echo for members of Churchill's secret army, who buried arms and explosives throughout south-east Essex to come forward.

'Mention of a cache hidden in a cave in the Billericay area jogged the memory of Stan Potter, Mr Potter of Ferry Road, Hullbridge, remembered his father, Harry, a sergeant, telling him of guns and ammunition being stored alongside the railway line at Billericay Station. Mr Potter said 'There were enough Bren guns and machine guns stored underneath the railway bridge to start World War Three.'

Harry Potter? That boy wizard certainly gets around. But then, the story of the Essex stay-behinds would not look out of place in the imaginative fiction of J K Rowling.

Fingringhoe Auxiliary Unit

In Tales of Peter Potter as Told to Hugh Frostick, Peter talks of being in Fingringhoe's Home Guard. The Captain was Mr Tippett who, in civilian life, worked as Tiptree's bank manager! George Simpson was a sergeant and the other members were Keith Radford, Gordon Harrington, John King and Dr Heggett. Peter Potter - only 14 when war broke out - and Peter Hopkins, both too young to be 'called up' initially, were also members. Peter Potter was to lie about his age at the age of 17 and signed up to the RAF becoming a Warrant Officer in 1943 and part of 626 Squadron.

The Home Guard met at Fingringhoe Village Hall which was an old WW1 army hut and they were all given a rifle with five rounds of ammunition and used to have target practice in the sand pit off Ballast Quay Road.

Peter (born in 1925) describes how, as a young man, prior to call up, he was a member of the Fingringhoe Auxiliary Unit for just three months. The Fingringhoe Auxiliary Unit, known as Colchester South, was sited near the Colne estuary being the most likely place locally an invasion force might attempt to come to shore.

Peter's Dad, Walter Louis Potter, of South Green Farm, and James McNair (Mac) of Plane Hall Farm, both farmers, were in the Unit. Peter remembers his father had a commando dagger, a Smith and Wesson .38 revolver and later on a Sten gun.

The man in charge was Geoffrey Green, known as 'Buller'.

Geoffrey was a Lieutenant in the Lancashire Fusiliers in WW1. He was born in Fingringhoe hall ... [and] was known locally as "Buller". He joined the Lancashire Fusiliers as soon as he could but was not allowed to go to France until he was 17 in 1916. He remained in France until the War ended and was twice wounded. During the Second World War he commanded a very secret section of the Home Guard given the task of carrying out assassinations & sabotage in the event Germany had invaded. Memorial Profiles: Edwin Sparrow Mersea Museum [ GREEN Daniel Abbott.pdf ]

Other members included Buller's cousin, Croyden Green, a mechanic, who had served in WW1 as a bombardier in the Royal Horse Artillery. He was Buller's second in command. Tom Cook was the local coal merchant and provided the transport for the patrol, Harry Harrington who died of leukaemia while in the Unit had been a stretcher bearer with the Royal Field Artillery in WW1, Albert Wagstaff, a carpenter, and Bob Allen completed the Unit.

Mac's brothers were in other Auxiliary Units in Essex, Wrabness and Ramsey, Horsley Cross and Earls Colne.

During Peter's three months in the Unit he was trained in explosives and recalls the Auxiliary manual detailing everything they needed to know about explosives. It had a deliberately deceptive title on the cover 'Countryman's Diary 1939'.

A Colchester Gazette article following Peter Potter's death in 2019 at the age of 94 re-tells one of Peter's stories about their training in using explosives.

They once blew up a section of old railway line and used a bit too much explosive and a large section of railway ended up landing in a nearby house. Colchester Gazette 4th November 2019

The Operational Base at Fingringhoe seems to have moved, possibly twice. There was one at Ballast Quay. Many years later, in 1980, Buller showed the remains of it to his nephew who recalled a shaft with a corrugated iron chamber. It seems after the war it was damaged by badgers digging their sett and subsequently was swept away by gravel extraction. Peter Potter described it as being 400 - 500 yards from any habitation with three rooms, two of which, the kitchen/living room/workshop and the sleeping quarters with 4 bunks had 100 foot long escape tunnels. The other room was to store explosives, ammunition and all their food and water. Given its facilities and size, it is likely this was the final OB. There was thought to be maybe an earlier dug-out at Jaggers Farm on the old rifle ranges but, as the war progressed the ranges were increasingly used by the military so it may have had to be abandoned. It was also reported there was a third Base in the West side of a copse opposite the Whalebone Inn on Plane Tree Farm which would seem probable as that was Jim Mcnair's farm.

The badge awarded to members of auxiliary units after the war. 201, 202 and 203 were the three battalions of the Home Guard to which Auxiliers belonged. Essex units belonged to 203.

Having looked at earlier periods of our history when invasion was threatened, I was surprised not to have found any evidence of a Unit on Mersea Island. From Roman times when a fort was built at East Mersea and, during the Napoleonic Wars when the Sea Fencibles were set up to guard the coast, the threat of enemy armies landing at Mersea was taken very seriously. On Mersea Museum website I found the following

There is little known about an Auxiliary Unit on Mersea Island. But, Hubert Cock was told by his father Herbert, that he had been part of an Auxiliary Unit. Herbert was a farmer at Brickhouse Farm West Mersea, who was in the Fusiliers in WW1 and wounded in France. It is not known where the unit had a hiding place. Other researchers think that East Mersea was an obvious place for an operation base, in easy communication with Operational Bases that were thought to exist at Thorrington and St Osyth.

In the event the invasion didn't happen, British success in the air and on the water and tactical errors on the part of the Germans put an end to any real threat of invasion by September 1940.

The Units were not stood down until the end of 1944 and most of the Auxiliers never spoke of their war-time work. Teams of Royal Engineers demolished most of the Operational Bases and those that have survived, albeit in a collapsed state, tend to be on private land.

The story of the Auxiliary Units adds new understanding to Churchill's famous speech of 4th June 1940 when he had to warn the populace of the possibility of invasion. We shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills; we shall never surrender.

Elaine Barker
Peldon History Project


"Churchill's Underground Army" by John Warwicker
"The Last Ditch" by David Lampe
"Tales of Peter Potter as Told to Hugh Frostick" by Peter Potter ISBN 9780995793804
Available from
"A Talent for Adventure" by Andrew Croft
"Auxiliary Units History and Achievement 1940 - 1944" by Major N.V. Oxenden M.C.
British Resitance Archive
British Resistance Organisation Museum, Parham, Suffolk
Colchester Evening Gazette - Tom King


John Morse
John Moore
Jimmy and Robin Strathern

Read more
Peldon's Preparations for a German Invasion

School days at Mersea in the War years

AuthorElaine Barker
SourceMersea Museum