Militia ( United Kingdom ) Eighteenth century and the Acts of Union . In 1707 , the Acts of Union united the Kingdom of England with the Kingdom of Scotland . The Scottish navy was incorporated into the Royal Navy . The Scottish military ( as opposed to naval ) forces merged with the English , with pre - existing regular Scottish regiments maintaining their identities , though command of the new British Army was from England . The threat of Ireland ' s belligerent ( Protestant ) militia to copy the American colonists if Irish demands for free trade were not met ( and Britain ' s inability , after years of war overseas , to easily stop them ) , would be the cause of the Kingdom of Ireland being admitted into the United Kingdom in 1801 . The Militia Act of 1757 created a more professional force . Better records were kept , and the men were selected by ballot to serve for longer periods . Proper uniforms and better weapons were provided , and the force was ' embodied ' from time to time for training sessions . The militia was widely embodied at various times during the French and Napoleonic Wars . It served at several vulnerable locations , and was particularly stationed on the South Coast and in Ireland . A number of camps were held at Brighton , where the militia regiments were reviewed by the Prince Regent . ( This is the origin of the song " Brighton Camp " . ) The militia could not be compelled to serve overseas , but it was seen as a training reserve for the army , as bounties were offered to men who opted to ' exchange ' from the militia to the regular army . Irish militia . The Parliament of Ireland passed an act in 1715 raising regiments of militia in each county and county corporate . Membership was restricted to Protestants between the ages of 16 and 60 . In 1793 , during the Napoleonic Wars , the Irish militia were reorganized to form thirty - seven county and city regiments . While officers of the reorganized force were Protestant , membership of the other ranks was now made available to members of all denominations . Scottish militia . In the late Seventeenth century came calls for the resurrection of militia in Scotland that had the understated aim of protecting the rights of Scots from English oppression . The 1757 Militia Act did not apply in Scotland . The old traditional system continued , so that militia regiments only existed in some places . This was resented by some and the Militia Club , soon to become the Poker Club , was formed to promote the raising of a Scottish militia . This and several other Edinburgh clubs became the crucible of the Scottish Enlightenment . The Militia Act of 1797 empowered Scottish Lord Lieutenants to raise and command militia regiments in each of the " Counties , Stewartries , Cities , and Places " under their jurisdiction . Nineteenth century . Although muster rolls were prepared as late as 1820 , the element of compulsion was abandoned , and the militia was transformed into a volunteer force . It was intended to be seen as an alternative to the army . Men would volunteer and undertake basic training for several months at an army depot . Thereafter , they would return to civilian life , but report for regular periods of military training ( usually on the weapons ranges ) and an annual two week training camp . In return , they would receive military pay and a financial retainer , a useful addition to their civilian wage . Of course , many saw the annual camp as the equivalent of a paid holiday . The militia thus appealed to agricultural labourers , colliers and the like , men in casual occupations , who could leave their civilian job and pick it up again . Until 1861 the militia were an entirely infantry force , but in that year a number of county regiments were converted to artillery . In 1877 the militia of Anglesey and Monmouthshire were converted to engineers . Under the reforms introduced by Secretary of State for War Hugh Childers in 1881 , the remaining militia infantry regiments were redesignated as numbered battalions of regiments of the line , ranking after the two regular battalions . Typically , an English , Welsh or Scottish regiment would have two militia battalions ( the 3rd and 4th ) and Irish regiments three ( numbered 3rd - 5th ) . The militia must not be confused with the volunteer units created in a wave of enthusiasm in the second half of the nineteenth century . In contrast with the Volunteer Force , and the similar Yeomanry Cavalry , they were considered rather plebeian . The Special Reserve . The militia was transformed into the Special Reserve by the military reforms of Haldane in the reforming post 1906 Liberal government . In 1908 the militia infantry battalions were redesignated as " reserve " and a number were amalgamated or disbanded . Numbered Territorial Force battalions , ranking after the Special Reserve , were formed from the volunteer units at the same time . Altogether , 101 infantry battalions , 33 artillery regiments and two engineer regiments of special reservists were formed . Upon mobilisation , the special reserve units would be formed at the depot and continue training while guarding vulnerable points in Britain . The special reserve units remained in Britain throughout the First World War , but their rank and file did not , since the object of the special reserve was to supply drafts of replacements for the overseas units of the regiment . The original militiamen soon disappeared , and the battalions became training units pure and simple . The Special Reserve reverted to its militia designation in 1921 , then to Supplementary Reserve in 1924 , though the units were effectively placed in " suspended animation " until disbanded in 1953 . The Militiamen . The name was briefly revived in 1939 , in the aftermath of the Munich Crisis . Leslie Hore - Belisha , the then Minister of War , wished to introduce a limited form of conscription , an unheard of thing in peacetime . It was thought that calling the conscripts ' militiamen ' would make this more acceptable , as it would render them distinct from the rest of the army . Only single men of a certain age group were conscripted ( they were given a free suit of civilian clothes as well as a uniform ) , and after serving for about a year , would be discharged into the reserve . Although the first intake were called up , the war broke out soon after , and the militiamen lost their identity in the rapidly expanding army . Modern survivals . Three units still maintain their militia designation in the British Army , two in the Territorial Army and one in the Army Cadet Force . These are the Royal Monmouthshire Royal Engineers ( formed in 1539 ) , the Jersey Field Squadron ( The Royal Militia Island of Jersey ) ( formed in 1337 ) , and the Royal Alderney Militia ( created in the 13th century and reformed in 1984 ) . Additionally , the Atholl Highlanders are a ( ceremonial ) private army maintained by the Duke of Atholl — they are the only legal private " army " in the United Kingdom . Colonial Militias . England had raised militia forces in its settled colonies in the New World immediately upon establishing its Trans - Atlantic Empire in the first decade of the Seventeenth century . Whereas militias in England remained little used during the following century , those in North America would play major roles . In numerous actions fought with hostile Native nations , the militia were the primary English force in the field , as professional help was far from hand . Even when the English Empire became the British Empire , and regular forces began to become available for garrison duty , Militias were still a vital part of Britain ' s military power in the Americas , and British victory over Spain and France , and its resulting hegemony in North America , could not have been realised without the colonial militias ( and the aid of Native allies ) . It was the presence of this Militia that allowed thirteen American colonies to launch the secessionist American War of Independence . In Bermuda , with no native population , the Militia followed a tracectory more like that in Britain , finally becoming moribund after the American War of 1812 , by when the build - up of regular forces had removed the demand for the militia . Nonetheless , in first century of settlement , Bermuda ' s militia had maintained the colonies sole defence , manning numerous fortifications and coastal batteries even in times of peace , and calling up all available manpower in times of war .