The First Fourth and First Fifth Battalions, the Territorial battalions, fought in the disastrous Campaign in Gallipoli in 1915.

The 1/5th Battalion was recruited in north Norfolk, including one company from the Royal Estate at Sandringham. On the 12th August the Battalion was part of an attack on Turkish positions inland from Suvla Bay. They received conflicting orders and advanced beyond the point where they could be supported by other troops. They were surrounded and suffered extremely heavy losses. Their unmarked graves were found in 1919. Despite the facts being published immediately after the war, the fate of the 1/5th Bn has given rise to all kinds of wild speculation and myths.

The remaining soldiers from these battalions were brought up to strength by reinforcements and went on to fight in Egypt and Gaza advancing north towards Jerusalem where they remained until the end of the War.