We’re proud of our long heritage at Ordnance Survey (OS) and that our teams contributed to the war efforts in the 20th Century. We have a memorial at head office commemorating the 123 people who lost their lives from OS during both world wars and gather each year to remember them. We supported the war efforts in many ways, including printing 33 million maps to show trench positions during World War One.
What you may not know is that in 1917-18, 46 women from the Overseas Branch of Ordnance Survey crossed the channel and arrived at the frontline to help set up a map making factory.
By 1917 OS needed to meet growing demand for maps of the German trenches and overcome the supply issue of getting them from Southampton to the Western Front. War leaders worried that ships carrying maps from Southampton might be sunk in the Channel, so in 1917 formed the Overseas Branch of Ordnance Survey (OBOS). This was a unit of 103 civilian men (from the Corp of the Royal Engineers) and 46 women (under the Queen Mary’s Army Auxilliary Corp). They made a bold decision to start map production in a factory close to the front line at Wardrecques in France.
The factory was next to the Aire Canal, meaning that consignments from England could be transported to the site to set up the printing presses so production could start. The advance party arrived on 15 December 1917, followed by the main body on 28 February 1918, and printing started on 7 March. The men and women were housed in wooden huts and a nearby hostel.
One of the 46 women was Martha Green. She was originally from Ancoats in Manchester and was the eldest of 16 children. She was a book binder by trade, but at the age of 24 she enlisted and went over to the OS factory on the front line to help produce the maps.
Work here for both men and women was hot and heavy. While some of the women had experience on printing with linotype presses – more had not and were assigned to the less-skilled tasks of folding, binding and working the perforation machine. Those that did work on the machines described it as being hard work. Working shifts of eight hours on and eight off and not being able to leave the machines until someone had come to relieve them. Many were said to have gone swimming in the canal during that summer to cool down.
The move to the front was a successful one. At its peak we produced 300,000 paper maps a week from the factory and distributed them among Allied forces while the battle raged on.
On 21 March the German offensive in the North began. Staff were reported to ‘have worked around the clock’ following the German offensive on the Somme in April 1918. As fighting began to close in, OS decided to evacuate from the frontline to another factory in (Wimereux, near Boulougne), with the last day of printing on 8 June. During this short period we produced over a million battlefield maps. The accuracy of the data on these maps were vital in helping to destroy German artillery.
By careful planning, map production continued without interruption and the wooden buildings were dismantled and re-erected at Wimereux. Shortly after their departure from Wardeque three bombs fell exactly on the former site of the hostel.
Conditions at Wimereux were spartan and the work exhausting, but believing that they would be there for some time, the staff settled in and did their best to make the place homely. A piano was obtained and the Queen Mary’s Army Auxiliary Corps dances (with officers of the OS cordially invited) were hosted in the recreation hall.
On 8 August the final allied offensive began and continuous shift work by an increased staff was necessary to meet the massive demand for maps in the final stages of the war. The signing of the Armistice on 11 November brought the need for trench maps to an abrupt end, but the machines were turned over to a new use, printing small-scale maps of Germany, for use by the allies.
Although only in existence for the last stages of the war, the Overseas Branch of the Ordnance Survey printed almost 3 million maps.
Martha Green left OS at the end of the war and got married, settling in Gorton in Manchester and having one son. She died in 1968.
You can buy a selection of commemorative trench maps available on the OS shop