 The brigade was attached to the Wessex Division and was composed of four battalions of the Hampshire Regiment, the 4th (Winchester), 5th (Southampton), 6th (Portsmouth) and 7th (Bournemouth).The Wessex Division was mobilised in early August 1914 and was sent overseas to British India in September to free up Regular Army troops for service on the Western Front in France and Belgium.In May 1915 the division was numbered as 43rd (Wessex) Division and the brigade was also numbered, becoming 128th (1st Hampshire) Brigade and the battalions became '1/4th Hampshires', for example, to differentiate them from their 2nd Line duplicates, the 134th (2/1st Hampshire) Brigade of the 45th (2nd Wessex) Division.