The battle was fought on a front from Courcelette in the east near the Albert–Bapaume road, to Thiepval and the Schwaben Redoubt (Schwaben-Feste) in the west, which overlooked German defences further north in the Ancre valley and on the rising ground towards Beaumont Hamel and Serre on the other side of the river.

Thiepval Ridge was fortified and the German defenders fought with great determination, while British infantry–artillery co-ordination declined after the first day, due to the confused nature of the fighting in the maze of trenches, dug-outs and shell-craters.

[1] The British pushed on towards Stuff and Schwaben redoubts until the end of the month and Reserve Army attacks resumed in the Battle of the Ancre Heights, which began on 1 October.

The British had made better use of their artillery and although German artillery ammunition consumption in September rose to 4.1 million shells from the 1.5 million fired in August, much of the ammunition was wasted on unobserved area bombardments, while defensive barrage fire was limited to three-minute periods; up to 25 per cent of the German guns became unserviceable in battle, due to mechanical failure.

Staufen Riegel had been dug as a supply route to Staufenfeste (Stuff Redoubt) and was on the reverse slope, which proved a considerable advantage against an attack from the south.

Reserves could be sheltered nearby at Baum Mulde (Boom Ravine), which was difficult for British artillery to bombard from the south, because of the obstruction of the ridge.

In the long periods of poor visibility, artillery observation aircraft were grounded, which made British bombardments even more inaccurate but the Marine-Brigade still had a stream of casualties caused by shellfire.

At 12:30 a.m. Brigadier-General Elmsley, the 8th Canadian Brigade commander, reported that the wire in front of Regina Trench was uncut, which led to the artillery continuing the wire-cutting bombardment up to the last minute.

The British artillery lifted towards Baum Mulde and Miraumont and the 8th Division troops saw waves of Canadian infantry advancing, while they were being relieved by the Marine Brigade.

The 1st Brigade on the right with two battalions, took the front trench of the Le Sars line from Dyke Road to 400 yd (370 m) beyond the Quadrilateral, then repulsed a counter-attack with artillery-fire.

As the Canadians reorganized before resuming the attack on the Quadrilateral, a heavy German bombardment fell in the area and a counter-attack began from two directions.

Part of the 7th Canadian Brigade reached Regina Trench, began to bomb westwards and also worked up the West Miraumont road but was eventually forced back by German counter-attacks.

The fire, from 200 heavy guns and howitzers and the field artilleries of seven divisions, was found to have severely damaged Regina Trench and cut most of the wire.

East of the Courcelette–Pys road, a defensive flank was formed, with outposts pushed forward from Regina Trench; the left-hand battalion linked with troops from the 18th (Eastern) Division.

Gough pointed out that maintaining the momentum of an attack required that succeeding waves and reserves not wait for opportunities to intervene in the battle, because communication delays left them with no time to act.

Corps headquarters also had the benefit of air observation and less need of direct communication with troops on the battlefield, since their main role was counter-battery artillery-fire, which was independent of the infantry battle.

The Canadians suggested that the first wave should not carry tools but a light load of 120 rounds of ammunition, two hand grenades, two days' rations and a ground sheet.

The importance of carrying enough hand grenades was stressed, since uncut wire forced the attackers into German communication trenches, where many more were used to fight forward compared to an advance on the surface, which used up the stock intended to repel counter-attacks.

The value of Lewis guns and enough ammunition was emphasised in many reports, as was the importance of moving them forward quickly, to support the infantry and engage German counter-attacks.

Opinion was divided over the Stokes mortar because of its rate of fire; each bomb weighed about 11 lb (5.0 kg), which meant that it was impractical to carry many forward in an attack.

1,680 of the men are identified as British, 564 Canadian, 35 Australian, one American airman and there are 1,077 burials of unknown soldiers, with special memorials to 14 casualties believed to be buried among them.