Royal Horse Artillery The regiments of the Royal Horse Artillery ( RHA ) , dating from 1793 , are part of the Royal Regiment of Artillery ( commonly termed Royal Artillery ) of the British Army . Horses are still in service for ceremonial purposes but were phased out from operational deployment during the 1930s . History . In 1793 , in the course of the French Revolutionary Wars , Great Britain and allied European powers declared war on France over French occupation of the Rhine delta and Antwerp , precipitating the Flanders Campaign . Britain remained in conflict with France for almost 22 years , during which time significant progress was achieved in artillery development . The first two troops of Horse Artillery ( A – later entitled " The Chestnut Troop " – and B ) were raised in January 1793 at Goodwood , East Sussex , by the Master - General of the Ordnance , the 3rd Duke of Richmond , to provide fire support for the cavalry . They were joined by two more troops in November 1793 . Each troop had six 6 - pounder guns . All RHA personnel were mounted . Included in the establishment were 45 drivers and 187 horses , making it the first self - contained fighting unit of artillery . Initially , horses were hired with civilian drivers . In 1794 a Driver Corps was raised which , however , did not formally become a unit of the Royal Artillery until after Waterloo . There were many disadvantages of the divided control until horses and drivers were organised into the RHA troops . Another development was the formation of a headquarter staff providing a channel between the regiment and the Board of Ordnance . Captain John Macleod was the first brigade major and became the first deputy - adjutant - general in 1795 . By 1806 , eleven troops had been formed , with ten companies of the Royal Irish Artillery incorporated , as the Seventh Battalion , after the union with Ireland in 1801 . The regiment wore light cavalry uniforms of blue with gold lace and red facings . Their overalls were grey with a red stripe and on their heads they wore the distinctive " Tarleton " helmets . If needed , they carried 1796 light - cavalry sabres . The RHA has acquitted itself with distinction in the great wars of two centuries , the Napoleonic Wars , the Indian Mutiny , the Crimean War , the Peninsular War , the Anglo - Zulu War , the Boer War , World War I and World War II . In 1859 , the term " battalion " was replaced by " brigade " . ( This in turn was replaced by " regiment " in 1939 . ) The five Horse Artillery brigades consisted of two batteries each . Between 1899 and 1924 , the Royal Artillery was divided , with the creation of the Royal Field Artillery which utilised horse for its medium - calibre guns . When the Territorial Force was created in 1908 , artillery units of the old Volunteer Force were converted into foot , horse , and garrison batteries . There were 14 batteries of horse artillery , 12 of which belonged to the RHA , the remaining two being provided by the Honourable Artillery Company . Territorial batteries were of four guns each rather than the six guns of regular batteries . The principal weapon of Territorial RHA units was the Ordnance QF 15 pounder although the Ordnance BLC 15 pounder was issued to some second - line RHA units formed in 1914 . At the outbreak of World War I the regular RHA comprised twenty - five batteries , eleven of those serving in India with the Indian Army . They were equipped with the Ordnance QF 13 pounder . In the 1920s , development of trucks and track vehicles brought an end to operational use of horses . By 1927 , medium artillery was drawn by tractors instead of heavy draught horses . By 1937 , nine field brigades had been mechanised as well as a brigade of RHA . The last battery to be mechanised was K Battery , in 1939 . Today , the ceremonial King ' s Troop alone retains the glamour of the mounted batteries . At the onset of World War II , recruits were instructed that " the role of the Royal Artilleryman is , as it has ever been , to fight his gun , forgetful of self , to the last round in support of other arms . " The RHA today . There are currently four separate regiments that wear the cypher ( cap badge ) of the RHA : The Royal Horse Artillery has provided the Queen ' s Guard on three occasions : The King ' s Troop provides the Queen ' s Life Guard in Whitehall for three weeks in August each year while the Household Cavalry Mounted Regiment goes away for summer training . Order of precedence . When on parade with its guns , the Royal Horse Artillery takes precedence over every other regiment and corps in the British Army , and parades at the right of the line . Otherwise , it immediately follows the Household Cavalry .