The RGA were the 'technical' branch of the Royal Artillery who were responsible for much of the professionalisation of technical gunnery that was to occur during the First World War.

Other than mounted or unmounted dress, the obvious distinction in uniform was by the shoulder title badges: RA (for the branch tasked with managing ammunition dumps and supply to units in the field); RGA; RFA; and RHA.

The Militia, which had become a paper tiger, changed from a conscripted force to one in which recruits voluntarily engaged for a term of service.

The invasion scare also led to the re-establishment of the Volunteer Force as a permanent (though only part-time, except when embodied for emergencies) branch of the British military.

This force (which differed from the Militia primarily in that its volunteers did not engage for a term of service, and might quit with fourteen days notice, except while embodied) contained a mixture of artillery, engineering and infantry units.

During the latter half of the Nineteenth Century, the military forces were re-organised through a succession of reforms, with the Board of Ordnance abolished after the Crimean War.

Its military corps, including the Royal Artillery, as well as its civilian Commissariat, transport and stores organs were absorbed into the British Army.

After 1919 all Royal Garrison Artillery personnel were classified as mounted men, whether serving in horse-drawn, mountain or tractor-drawn batteries.

)[7] Fixed artillery (that which is not meant to move, other than for the purpose of aiming) was placed in forts and batteries in locations where they might protect potential targets (ports, cities, etc.)

Coastal artillery relied primarily on high velocity guns, capable of striking out at ships at a great distance, and penetrating their armour.

Mobile (field) artillery pieces were sometimes used that could be quickly re-deployed as required between fortifications that were not permanently manned or armed.

By the start of the 20th century, the increasing size of the capital ships of the world's largest navies, and of the guns they wielded, was already sounding the death knell of coastal artillery.

In August 1914 the responsibility was still split, with the Royal Garrison Artillery employing 30 officers and 312 men on air defence duties.

[11] The RGA grew into a very large component of the British Army, being armed with heavy, large-calibre guns and howitzers that were positioned some way behind the front line and had immense destructive power.

Later in the war, advances in the science of gunnery enabled guns to be aimed at co-ordinates on a map calculated with geometry and mathematics.

The RGA was often supported by the Royal Flying Corps (RFC) who had devised a system where pilots could use wireless telegraphy to give corrections of aim to the guns.

The RFC aircraft carried a wireless set and a map and after identifying the position of an enemy target the pilot was able to transmit messages such as A5, B3, etc.

In the Far East, the growing threat of the Imperial Japanese Navy and Japan's military adventures in China meant that coastal artillery defences were increased, notably at Singapore where the Singapore Naval Base was constructed, and Regular Army coastal artillery units remained.