The racecourse at Blackwell was chosen as a base for the Lonsdale Battallion in late 1914, the base at The Swifts judged to be too prone to flooding. The racecourse was well drained and had plenty of space for training, accommodation and office space. The Citizens' League and local press played an important role in preparing the racecourse for its new purpose, arranging water supplies, catering and encouraging the public to give their time to stuff pillows or make donations of furniture.
There were frequent training demonstrations and marches to encourage more men to enlist with the Lonsdale Regiment. Until 1916, recruits could choose which battalion they joined and many opted for more established regiments over the ‘pals’ battalions like the Lonsdales. W. Monkhouse, who was based at Blackwell also raised his concerns that “The Lonsdale Bn is also out of favour at present as the 11th is still in England”.
The racecourse provided a home and training ground to the Lonsdale Battalion until the regiment was mobilised to France in November 1915. They were bound for the Somme and arrived at the front line in late December. 800 troops from the Lonsdale Battalion were engaged on the first day of fighting in the Battle of the Somme on 1 July 1916. In this one day the battalion suffered more than 500 casualties, including 23 of 26 officers.
A detachment of the battalion remained at Blackwell for the duration of the war.