 Complete the following phrase:  The City of London Yeomanry Rough Riders was a yeomanry regiment of the British Territorial Army, formed in 1901 from veterans of the Second Boer War. In World War I it served dismounted in the Gallipoli Campaign but reverted to the mounted role in the Senussi campaign, at Salonika and in Palestine. It ended the war as a machine gun unit on the Western Front. In the interwar years it was reduced to a battery in a composite Royal Horse Artillery unit in London, but in the period of rearmament before World War II it was expanded into a full regiment of light anti-aircraft artillery. It served in this role during The Blitz and later in the 