Thomas Cook was born in Cock Gate, Bircher about 6 miles from Eardisland, but moved to Kington after his father died. At 14, he was living in Eardisland, working as an errand and delivery boy around the village. He joined the army in Hereford at the very beginning of the War. Evidence suggest he was underage.
In 1915 Thomas Cook left England to fight in the Gallipoli campaign. The 1/1st Herefords embarked on 16th July at Devenport on SS Euripedes. Their divisional artillery had been left behind in England under orders for France, and the Division had no other wheeled transport and no horses. There were 29 officers and 969 other ranks. On reaching Port Said the Battalion was reduced to 25 officers and 750 Other Ranks and these men went on to land at 'C' beach at Suvla Bay.
The landing began at 0720 hrs, with the Herefords part of the 53rd Welsh Division, commanded by Major-General Lindley. Without artillery support or sufficient transport the landing became difficult. A lack of planning resulted in the 53rd was broken up and dispersed to wherever help seemed needed.
Part of the Battalion had remained offshore pending a second assault on Day 2, 10th August. In that action, Thomas Cook was wounded during the beach landing. He was evacuated to a Field Hospital but died shortly after.