The Battalion was raised on 6th September 1914 at Dorchester. In the hectic fortnight that followed prior to the move to Wareham over 1,000 men joined. Unlike the 5th Battalion, most of whose recruits were local to Dorset, only three hundred were from the County, the majority of whom joined D Company. 400 volunteers came from London, another 400 from Warwickshire and 70 miners came from South Wales.
The Battalion formed part of the 17th Northern Division, whose battalions – mainly from northern regiments – undertook their training in and around the hills, heaths, and pine woods surrounding Bovington. Originally earmarked as Pioneers, the 6th Dorsets expressed a wish to be a fighting unit and the 7th York & Lancasters assumed the pioneer role.
Although initially the Division had been selected for Home Defence duties, this decision was reversed and they proceeded to France, landing at Boulogne on 14th July 1915, concentrating near St Omer. They moved into the Southern Ypres salient and, after their initial trench familiarization, went into the line in that area.
In the spring of 1916 they saw action at the Bluff, south east of Ypres on the Comines Canal, before moving south to the Somme. Here they fought in the Battle of Albert, in which the Division captured Fricourt, and in the battle at Delville Wood.
In 1917 they moved to Arras and saw action in The First and Second Battles of the Scarpe and The Capture of Roeux. In late summer they returned to Flanders and fought in The First and Second Battles of Passchendaele.
In 1918 they fought in the Battles of St Quentin, Bapaume, Amiens, Albert, Havrincourt, Epehy and Cambrai before taking part in the British pursuit of the German Army to the Selle. They then fought in the Battles of the Selle and the Sambre. The Armistice found the Division south east of Maubeuge and, after a short spell west of Le Cateau, on 6th December they moved back to near Amiens and went to billets around Hallencourt. Demobilisation began in January 1919.
Their long war cost the 6th Dorsets 1,000 lives – more than the entire strength of the Battalion. Nearly half of these losses were incurred in 1918 with exceptionally high losses in the final advances of the last three months of the conflict.
After the Armistice the 6th Battalion were eventually redeployed to Frucourt. Most of the men were demobbed over the coming months while the remnants of the Battalion eventually reaching Dorchester on 26th May 1919, where the 6th were disbanded.