On 6 August 1914, less than 48 hours after Britain's declaration of war, Parliament sanctioned an increase of 500,000 men for the Regular Army, and on 11 August the newly appointed Secretary of State for War, Earl Kitchener of Khartoum issued his famous call to arms: 'Your King and Country Need You', urging the first 100,000 volunteers to come forward.

By 15 September, 80 men had been enrolled for the battery, many drawn from the shipbuilding and engineering firms in Hull, while drivers came from the rural villages of the East Riding.

It reached its full war establishment by mid-December, when it was authorised to recruit an additional depot section to supply reinforcements.

[2][4][11][15] Captain McCracken left on 25 May 1915 to become adjutant of the Humber Garrison and was replaced as CO by Lieutenant-Colonel H.M. Slater, RGA, who commanded the training brigade at Hedon.

[2][21][24][25][26] XXXVIII Brigade embarked some of its lorries and stores aboard SS Anselma da Larrinaga at Avonmouth Docks and the rest of men, lorries and guns aboard HM Transport Huntsgreen (formerly the German Norddeutscher Lloyd shipping line's Derfflinger) at Devonport Dockyard on 7–8 February.

11th (H) Bty reinforced 2nd Division at Kondoa Irangi on 3 June after a long march through rough country, crossing the Pienaar Heights and several rivers where motor vehicles had to be towed through the water.

From 6 June the fire was directed by newly arrived Voisin aircraft from No 7 Squadron Royal Naval Air Service.

The rest of 11th (H) Bty reached Mpwapwa on 18 August, but was held up there by lack of petrol and the damage done to its vehicles by the bad roads.

The two guns were towed by FWD lorries, but the ammunition column was drawn by oxen and manned by 134th (Cornwall) Heavy Bty.

The battery went onto action at a range of 2,500 yards (2,300 m), where the howitzers' heavy Lyddite shells proved decisive, causing the German Askaris to break and flee.

The force then took Morogoro on the Central Railway, where 13th (H) Bty went into camp on 28 August, while Smuts attempted to surround the enemy by pushing down both sides of the Uluguru Mountains with 1st and 3rd Divisions.

[48][49][50][51] Meanwhile, 14th (H) Bty remained at Mbyuni until August when it went by train to Tanga and embarked on SS Montrose for Zanzibar and then on to Dar es Salaam where it was accommodated in the German artillery barracks.

However, the advance bogged down into static fighting at Kibata Fort, where the infantry took heavy casualties from shellfire until the two howitzers could finally be got forward on 1 January 1917.

Towards the end of June 1917 the whole battery moved (using porters to draw the guns in the absence of motor vehicles) to Rombo to join No 2 Column of Deventer's force.

[58] The advance began on 4 July, the columns pursuing the German commander Paul von Lettow-Vorbeck and his small force, which engaged them with rearguards, but never stayed long enough for the battery to get into action.

Mobility was improved in mid-July when the Napier and FWD vehicles arrived, and the battery crossed over to No 1 Column, which was spearheading the pursuit.

Roads were bad, necessitating the use of porters to help the vehicles, and the battery remained inactive at Mssindy throughout August while the infantry cleared the surrounding area.

On 11 November the battery supported an infantry attack on Chiwata Hill and then shelled German positions over succeeding days.

Serjeant Arthur Cowbourne was awarded a Distinguished Conduct Medal for maintaining the telephone line between the OP and the column.

However, Maj Floyd objected and in July the battery was re-equipped with four modern 6-inch Mk XIX guns towed by Holt tractors, with an MT section of 16 Thornycroft lorries.

The battery landed at Le Havre on 16 July 1918 and deployed in the Lys sector under Fifth Army, where it came under regular gas shelling.

The success of the Battle of Amiens caused the Germans to withdraw from the Lys Salient and the battery had to move forward to new positions.

The gunners were unable to find suitable positions during the night of 24/25 September, and left their gun platforms beside the road under guard.

The battery targeted Usigny Dump, a German stores depot masked in a dip in the ground some 6 miles (9.7 km) away.

[86][87][88][89] Getting the artillery forward following these victories proved difficult, but 545th Siege Bty's Right Section was attached to 'Roberts Brigade', an ad hoc formation organised for the pursuit, and continued its bombardment on 10 October from Maurois railway station.

[91][92][93] 545th Siege Battery's guns had now fired so many rounds that their barrels required re-lining, and were sent to the Ordnance depot at Amiens on 27 October, thereby missing the Battle of the Sambre.

Serjeant Goodwin (ASC) and Lance-Bombardier Frank Dickens (545th Bty) were awarded the Meritorious Service Medal for their gallantry in throwing shells from a burning lorry.

[94] On 5 November, all heavy artillery batteries in XIII Corps' area were stood down and the men billeted in Le Cateau.