Britain declared war on Germany on 4 August 1914 and sent troops to northern France to stop the German advance through Belgium. By the end of the year, fighting was restricted to a line of trenches that stretched through Flanders and northern France, from the English Channel to Switzerland. This was known as the Western Front.

The British managed to hold on to Ypres, which was vital in maintaning access and control of the English Channel ports, but the Germans gained ground.

The British tunnelled into and under the hill and exploded five mines from the tunnels, which enabled them to take the hill.

The Germans made very slight gains towards Ypres. The battle was notable as being the first time chlorine gas was used. It was first used by the Germans.

The British used a creeping barrage to make small gains to break out of the Ypres Salient. The awful weather left the ground waterlogged and many drowned.

Notable for the extremely high casualties on both sides, the battles on both sides of the river of the Somme saw two new strategies by the British- the creeping barrage and the first use of tanks- but these had little impact.

In 1916, the British linked and expanded the underground tunnels and the movement of troops. The tunnels were used to launch the battle, which was initially successful but ended with little progress and high numbers of casualties on both sides.

This battle was notable for the first large-scale use of tanks, which were successful but were not backed up so the British were forced back