 Complete the following phrase:  The regiments first action of the war came during the Gallipoli campaign. Due to the terrain and the static nature of the fighting on the peninsula, it was felt that mounted units could not play a part; however, a number of light horse units were deployed in a dismounted role as infantry. The 10th Light Horse Regiment arrived at Gallipoli on 20 May 1915 and initially it was largely used in a defensive role. In August, however, the Allies attempted to break the stalemate, launching the August Offensive. The regiments action at the Nek during this offensive was immortalised in the final scenes of the 1981 Peter Weir film Gallipoli. It was also involved in the 