Volunteer Army (British)

The Volunteer Force was a citizen army of part-time rifle, artillery and engineer corps, created as a popular movement throughout the British Empire in 1859. Originally highly autonomous, the units of volunteers became increasingly integrated with the British Army after the Childers Reforms in 1881, before forming part of the Territorial Force in 1908. Most of the regiments of the present Territorial Army Infantry, Artillery, Engineers and Signals units are directly descended from Volunteer Force units.

Following the Crimean War, it was painfully clear to the War Office that, with half of the British Army dispositioned around the Empire on garrison duty, it had insufficient forces available to quickly compose and despatch an effective expeditionary force to a new area of conflict, unless it was to reduce the British Isles' own defences. During the Crimean War, the War Office had been forced to send militia and yeomanry to make up the shortfall of soldiers in the Regular Army. The situation had been complicated by the fact that both auxiliary forces were under the control of the Home Office until 1855.

Tensions rose between the United Kingdom and France following the Orsini affair, an assassination attempt on Emperor Napoleon III on 14 January 1858. It emerged that the would-be assassin, Felice Orsini had travelled to England to have the bombs used in the attack manufactured in Birmingham. The perceived threat of invasion by the much larger French Army was such that, even without sending a third of the army to another Crimea, Britain's military defences had already been stretched invitingly thin. On 29 April 1859 war broke out between France and the Austrian Empire (the Second Italian War of Independence), and there were fears that Britain might be caught up in a wider European conflict.

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