The British Army has played a central role in the long history of conflict and co-operation between Britain and Ireland. Here we explore some of the key moments in this difficult but fascinating story.
Fought between 1756 and 1763, this conflict can claim to be the original 'world war'. Franco-British fighting in North America and India became part of a general war in Europe with far-reaching consequences.
In the autumn of 1914, British soldiers fought alongside the Japanese in China. Their goal was the German naval base at Tsingtao, which finally fell in November after a two-month siege.
This unit was formed as the Women's Army Auxiliary Corps in 1917 to free up more men to fight in the First World War. It was the first time women had served in the British Army other than as nurses.
Field Marshal Sir Douglas Haig commanded the British Army when it achieved arguably its greatest victories, those over the Germans on the Western Front. But for many his leadership was marked by unacceptable losses.
In June 1916, a British military mission began recruiting a local force in neutral Persia. Its goal was to bolster Allied interests and prevent enemy influence in the region.
During 1915, the British and French undertook a series of unsuccessful attacks against the Germans on the Western Front. For both sides it was a tough learning experience.