City of London Yeomanry ( Rough Riders ) The City of London Yeomanry ( Rough Riders ) was a yeomanry regiment of the British Territorial Army , formed in 1901 and amalgamated in 1961 . The unit had originally been formed in 1900 as the 20th Battalion , Imperial Yeomanry , and designated for service in the Second Boer War . The battalion ' s adopted nickname of the " Rough Riders " was taken from the US cavalry regiment that fought in the Spanish - American War . An additional battalion , the 22nd Rough Riders , was then formed in 1901 , when the 20th Battalion was disbanded and the new regiment was formed from Boer War veterans . This regiment was retitled the City of London Imperial Yeomanry ( Rough Riders ) , with its headquarters at the Guildhall . The HQ later transferred to Finsbury Square , and the regiment , upon joining the newly established Territorial Force in 1908 , was again retitled as the 1st City of London Yeomanry ( Rough Riders ) . By the beginning of the First World War , the regiment consisted of four squadrons attached to the London Mounted Brigade . Two duplicate battalions were raised in 1914 and 1915 , designated as the 2 / 1st and 3 / 1st respectively . The 2 / 1st served with the 2 / 2nd Mounted Division , and the original 1 / 1st initially served as dismounted infantry in Gallipoli , where it fought in the Battle of Scimitar Hill . The battalion suffered heavy casualties before it was evacuated to Egypt , after which it moved to Salonika in 1916 . Following its return to Egypt in 1917 , the COLY participated in the Allied advance into Ottoman - controlled Palestine . In 1918 , it again expanded to form E Battalion , Machine Gun Corps , which served on the Western Front . After reconstitution in the Territorial Force in 1920 , the unit was reduced to a battery of the 11th ( Honourable Artillery Company and City of London Yeomanry ) Regiment , RHA . In 1938 , as World War II approached , the battery was then split off to form the 11th ( City of London Yeomanry ) Light Anti - Aircraft Regiment , RA , part of which served in a defensive role at Bentley Priory , the RAF ' s Fighter Command headquarters in Stanmore , Middlesex . The rest of the regiment remained in London during the Blitz . Service in North Africa and Italy followed from 1942 to the end of the war . The City of London Yeomanry was reconstituted in 1947 as an armoured regiment within the Royal Armoured Corps . A further conversion to infantry occurred in 1956 , when it became a battalion of the Rifle Brigade ( Prince Consort ' s Own ) . On 1 May 1961 , and given their geographical proximity , the Rough Riders amalgamated with the Inns of Court Regiment , to form the Inns of Court and City Yeomanry . In April 1967 , the Territorial and Army Volunteer Reserve ( TAVR ) replaced the old Territorial Army . Through Denis Healey ' s Defence Cuts , the new unit was then reduced in size to form 68 ( Inns of Court & City Yeomanry ) Signal Squadron , within the 71st ( Yeomanry ) Signal Regiment , Royal Corps of Signals . Although the new squadron did not inherit the freedoms of the boroughs that its predecessors had been awarded , it has maintained the Rough Riders ' rare privilege of providing a mounted escort to the Lord Mayor of London at the annual Lord Mayor ' s Show . The COLY heritage can also be seen in both the officers ' metal cap badge ( which shows the four Inns of Courts ' coats of arms overlaid by those of the City of London ) ; and in the cloth cap badge ( which shows the Inns of Court Regiment ' s Devil holding the Rough Riders ' cavalry spur ) . In 2009 , the IC & CY in turn merged with The Essex Yeomanry to form The Inns of Court & City and Essex Yeomanry ( ICCEY ) . References . External links last verified on 19 January 2009