The Sussex Royal Garrison Artillery and its successors were part-time coast defence units of the British Army from 1910 to 1932. Although the unit saw no active service, it supplied trained gunners to siege batteries engaged on the Western Front during World War I.
Origin
When the Territorial Force (TF) was created from the old Volunteer Force under the Haldane Reforms of 1908, the Kent and Sussex Royal Garrison Artillery was included as a new defended ports unit of the Royal Garrison Artillery (RGA). It was formed from companies drawn from the previous 1st Kent and 1st Sussex RGA (Volunteers) and its headquarters (HQ) was at Chatham, Kent. However, two years later the two Sussex companies were split off to form a separate Sussex Royal Garrison Artillery with the following organisation: HQ at 117 Gloucester Road, Brighton No 1 Company at Brighton No 2 Company at Watergate Lane, Lewes
The unit was responsible for the defended port of Newhaven in South Eastern Coast Defences, which was guarded by two 6-inch Mk VII guns mounted at Newhaven Fort.
World War I
Mobilisation
When World War I broke out on 4 August 1914 the TF coastal units mobilised and manned their defences. On 31 August 1914, the War Office (WO) authorised the formation of Reserve or 2nd Line units for each existing TF unit; each was prefixed '2/' to distinguish it from the 1st Line ('1/'). Initially these were formed from men who had not volunteered for overseas service, together with the recruits who were flooding in.
By October 1914, the campaign on the Western Front was bogging down into Trench warfare and there was an urgent need for batteries of siege artillery to be sent to France. The WO decided that the TF coastal gunners were well enough trained to take over many of the duties in the coastal defences, releasing Regular RGA gunners for service in the field. Soon the TF RGA companies that had volunteered for overseas service were also supplying trained gunners to RGA units serving overseas. Although complete defended ports units never went overseas, they did provide cadres to form units from New Army ('Kitchener's Army') volunteers for front line service. The Sussex RGA supplied cadres for 69th and 122nd Siege Btys in 1915–16 (see below), and 134th Siege Bty formed at Dover in 1916 is known to have had a nucleus of men from the Kent and Sussex RGA units. This may also have been the case for some of the numerous other siege batteries formed at Dover during the war.
This process meant a continual drain on the manpower of the defended ports units and in April 1917, the coastal defence companies of the RGA (TF) were reorganised. By this stage of the war, the Dover and Newhaven Defences of Eastern Command consisted of 1/1, 1/2, 2/1 and 2/2 Companies of the Sussex RGA and 1/3 and 2/3 Companies of the Kent RGA (the remainder of the Kent companies being in the Thames and Medway defences). These six companies were reduced to just two (Nos 1 and 2 Companies, Sussex RGA), given a slightly higher establishment (five officers and 100 other ranks (ORs)), and the 1st and 2nd Line distinction was abolished. At the end of the war the two companies were in No 10 (Kent & Sussex) Fire Control at Newhaven.
The TF was demobilised in 1919 after the Armistice with Germany and the Sussex RGA entered suspended animation.
69th Siege Battery
A company from the Sussex RGA provided half the personnel for 69th Siege Battery, RGA when it was formed on 9 October 1915, the remainder being New Army volunteers. Major A.J. Martineau of the Sussex RGA served as second-in-command. The battery landed in France on 1 April 1916 equipped with four 9.2-inch howitzers and joined 27th Heavy Artillery Group (HAG) supporting III Corps in Fourth Army.
Somme
Fourth Army was preparing for that year's 'Big Push', the Battle of the Somme, with III Corps facing the German redoubts in front of Ovillers. The final bombardment began at 06.25 on Z Day (1 July). However, the artillery had failed to knock out many of the machine gun positions, and as soon as the attackers went 'over the top' they began to take heavy casualties. 8th Division attacking up the Ovillers spur gained only a few footholds in the opposing lines, and it was impossible to renew the attack in the afternoon. The battery continued to support Fourth Army while the Somme offensive continued into the autumn.