World War One and its lasting legacy
5 August 2014 Last updated at 01:15 BST
The conflict lasted for four years and had an immense impact on British society, it also led to a new world order with the collapse of the Russian, Austro-Hungarian and Ottoman Empires.
The BBC's Fergal Keane has been assessing the continuing legacy of World War One.
Here you can watch more stories of World War One veterans and civilians: The Great War Interviews