On 12th August 1941, the Belfast News-Letter reported on a large-scale training exercise in Ulster. The realistic mock battle took place over the course of three days and spread over two counties in Northern Ireland. Photographs taken by Lieutenant J.R. Bainbridge name are captioned "Summit Exercises". By the end of the exercises, British troops in Northern Ireland were said to be prepared for anything and "at concert pitch".
This statement, and the exercise, was in direct response to an address by British Prime Minister Winston Churchill on 29th July 1941. Addressing the House of Commons at Westminster, he issues a warning to all armed forces during what he called “invasion season”. It was Churchill, the renowned orator, who first urged the forces to reach “concert pitch” by 1st September 1941.
Across a large swathe of the countryside, several thousand soldiers with military vehicles took part in the exercises. It was by far, the largest military training exercise Northern Ireland had seen to that date. As well as many British battalions, even the Local Defence Volunteers (later to become the Ulster Home Guard) played a role.
Every aspect of warfare was run through during the exercises; marching, fighting, eating, sleeping. All activities took place in the open with soldiers concealing themselves and their vehicles from the threat of attack. Thousands of vehicles also took part; tanks, cars, lorries, Universal Carriers all roaring through the countryside. Soldiers carried running repairs as they went along.
Down roads and lanes in towns and villages, soldiers lurked behind walls, hid in hedgerows, and filed long ditches. One battalion marched 28 miles through the Sperrin Mountains. A Motor Transport Company then took them into “battle” again before they had finished their roadside meal. Across the hills, another British battalion marched 45 miles in two days.
There they were, peering over walls, poking their heads out of the hedges, sleeping below trees, dodging in Indian file along the hedges and ditches, and roaring in their lorries by the light of the moon through sleeping Ulster towns, bringing up the rations from a railhead far away, doing running repairs to their lorries, their cars, their Bren carriers, bringing their field artillery into action here, there and everywhere – all the noise and movement of the modern military machine in a real Irish setting of green fields, brown bogs, and purple mountain.
In August 1941, British Troops in Northern Ireland conducted a large-scale military mock battle spread across Ulster and involving the Home Guard as guerrillas.