The Territorial Force was founded by Richard Burdon Haldane, Secretary of State for War, on April 1 1908.

They first saw action during the First World War on the Western Front, Egypt, Palestine and North Russia. The first of the TA's 71 Victoria Crosses was awarded in 1915 at Ypres to Second Lieutenant Geoffrey Harold Woolley in 1915 during the First World War.

The Territorial Force units were disbanded in 1918 to be later made into part of the Territorial Army.

The TA first saw action in the Second World War in Norway in 1940.

They served alongside the regular army in all theatres of war.

Having served in both world wars, Territorials have since served with distinction in Korea, Aden, Kosovo, Bosnia, the Gulf and Afghanistan.

Defence Secretary Des Browne said "This anniversary year - TA 100 - is the perfect opportunity to celebrate the contribution and commitment of our Territorial Army, to pay tribute to the veterans of the TA and to say 'thank you' to the 35,000 men and women currently serving with the TA.

"They are an integral part of our defence effort – both here at home and overseas." Chief of the General Staff (CGS) General Sir Richard Dannatt added: "The TA makes a significant contribution to operations as it has done throughout its 100 year history even as we speak, are sharing the demands and rewards of operational service in Iraq and Afghanistan.

Factfile

• The TA has around 36,000 soldiers throughout the UK and Gibraltar

• There were no females in the TA until after the Second World War. Now nearly 20 per cent of the TA are women

• The TA provides a high proportion of the Army's specialist functions (Engineers, Medical Services, Logistic support)

• Around 1,200 Territorials were deployed on operations during 2007 in Iraq, Afghanistan, Kosovo and Bosnia - this accounted for seven per cent of deployed soldiers

• Five TA soldiers have lost their lives while on active service in Iraq since 2003

• Three Territorials have lost their lives while on active service in Afghanistan since 2003

• Famous Territorials to have served during the force's history include Sir Winston Churchill; Billy Connolly; Basil Rathbone; Alexander Fleming; Lord Bill Deedes, and Airey Neave