War for Europe meant war for the world. Germany gambled that Britain might risk everything to protect her Empire - even victory on the Western Front. So, to divert British resources, maverick German commanders led the British a dance; across the Pacific, Africa and the Middle East.

The Ottoman Empire, Germany's ally, summoned all Muslims to Jihad - holy war - to overthrow Allied power in the Middle East. They proved a formidable foe, as the Allies found to their cost at Gallipoli and in the Middle East.

As the Germans and Austrians clashed with The Russians on the bitter Eastern Front, Italy became embroiled in a terrible slaughter.

The effect of the Great War shattered nations, inspired mass mutinies by desperate troops, caused great upheaval on the home front and changed the world forever.

Attrition, "lions led by donkeys", the slaughter only ceasing for a brief truce one Christmas - old, mistaken views of the war on the Western Front. In fact there was constant tactical evolutions; hundreds of generals died in action; some men adopted a system of "Live and Let Live", with countless informal local truces.

Over one million German troops were committed to Kaiserschlacht - the last great offensive of the war - while conflict still raged on many other fronts.

The First World War shaped the twentieth century. It sparked the Russian Revolution, and it launched America as a world power. The fault-line from its failed peace settlement led to a second terrible world war barely twenty years later.

The first months of the war on the Western Front were mobile, fast and dangerous; casualty rates were higher than with later trench warfare. The Germans were halted by the Allies at the Battle of the Mame, fell back to high ground and dug in. The Allies followed suit.

The war at sea was every bit as bitter as the war on land. The battle at Jutland proved inconclusive but the U-Boat menace threatened Britain as never before. Meanwhile, America entered the war.

The dramatic Allied victory at Amiens led to victory in just 100 days - and the signing of a bitterly-resented peace, while other nations stumbled towards their own ceasefire agreements.