The 66th Infantry Division was an infantry division of the British Army, which was active between September 1939 and June 1940 during the Second World War. In March 1939, after the re-emergence of Germany as a European power and its occupation of Czechoslovakia, the British Army increased the number of divisions within the Territorial Army by duplicating existing units. The 66th Infantry Division was formed in September 1939, as a second-line duplicate of the 42nd (East Lancashire) Infantry Division. The division's battalions were all raised in the Lancashire and Cumbria area.
It was intended that the division would remain in the United Kingdom to complete training and preparation, before being deployed to France within twelve months of the war breaking out. Instead, the division spent the majority of its existence guarding vulnerable points in the United Kingdom. By May 1940, the division had been assigned to the initial plan to defend the country against any potential German invasion. As a result of the rapid German victory on mainland Europe in 1940, the division was not deployed overseas. Once the British Army returned from France, it implemented experience gained from the campaign. This involved the break-up of several divisions, including the 66th Division, in order to bring others up to full strength.
Background
Throughout the 1930s, tensions built between Germany and the United Kingdom and its allies. During late 1937 and 1938, German demands for the annexation of Sudetenland in Czechoslovakia led to an international crisis. To avoid war, the British Prime Minister, Neville Chamberlain, met with the German Chancellor, Adolf Hitler, in September and came to the Munich Agreement, which accepted that the Germans would annexe the Sudetenland. Chamberlain had intended the agreement to lead to further peaceful resolutions to differences, but relations between both countries soon deteriorated. On 15 March 1939, Germany breached the terms of the agreement by invading and occupying the remainder of the Czech state.
On 29 March, the British Secretary of State for War, Leslie Hore-Belisha announced plans to increase the part-time Territorial Army (TA) from 130,000 men to 340,000 and double the number of divisions. The plan was for existing TA divisions, referred to as the first-line, to recruit over their establishments, aided by an increase in pay for Territorials, the removal of restrictions on promotion which had hindered recruiting, the construction of better-quality barracks, and an increase in supper rations. The units would then form a new division, referred to as the second-line, from cadres. This process was dubbed "duplicating". The 66th Infantry Division was to be created as a second line formation, a duplicate of the first line 42nd (East Lancashire) Infantry Division. Despite the intention for the army to grow, the programme was complicated by a lack of central guidance on the expansion and duplication process and issues regarding the lack of facilities, equipment and instructors. It had been envisioned by the War Office that the duplicating process and recruiting the required numbers of men would take no more than six months. In April, limited conscription was introduced. At that time 34,500 men, all aged 20, were conscripted into the regular army, initially to be trained for six months before being deployed to second line units. The process varied widely between the TA divisions, and was complicated by a lack of central guidance, as well as the lack of facilities, equipment, and instructors. Some were ready in weeks while others had made little progress by the time the Second World War began.