December 1914. The world is at war.

The First World War was the most brutal conflict the world had seen. Nine million combatants were killed in the space of four years.

In Ypres, Belgium, on Christmas Eve one of the defining incidents of the war took place.

The Germans decorated their trenches with Christmas trees and lit candles. They started singing carols.

British and French troops responded with their own carol singing. Greetings were shouted across no-man’s land, closely followed by tentative excursions out of the trenches.

Presents were exchanged, cigarettes were shared and even an impromptu game of football was started. Germany won 3-2. Hours later, war resumed and the men returned to trying to kill one another.

High ranking officers took a dim view of the unofficial truce, and stamped down on any future fraternisation with the enemy. Reports suggest that some who took part subsequently found it difficult to open fire on the men they had shared Christmas with.