At the outbreak of war in 1939, the General Post Office (GPO) controlled virtually all civil communications channels: mail, phone and telegram. The GPO was also the largest employer in the country, and its business was turned upside down when one third of GPO staff joined active service, within a few weeks of the declaration of war.

This upheaval in the Post Office reflected the changes brought by war to everyday British life. The bombing of sorting offices, telephone exchanges and railways could not be allowed to disrupt communications, which were now more important than ever.

The dedication of the GPO staff played a major role in preserving the normal functioning of the ‘home front’, helping to promote the domestic war effort and support military operations. Mail to the troops kept up all-important morale with news from home.

As a British government department the GPO took on new roles including the distribution of ration books, public information and food parcels to prisoners of war. The size of the telegraph network was tripled, setting up vital communications to enable the planning for D-Day.

GPO engineers brought their technical expertise to the building of ‘Colossus’ - the first ever electronic computer - to help crack the Lorenz codes of the Nazi High Command.

73,000 men and women from the GPO joined the services on the outbreak of war or soon after. Of these 3,800 never returned. Another 413 gave their lives whilst on Post Office service as civilians. Post Office workers received 700 decorations and awards.