Expedition to Hanover

The British Army during the Napoleonic Wars experienced a time of rapid change. At the beginning of the French Revolutionary Wars in 1793, the army was a small, awkwardly administered force of barely 40,000 men. By the end of the period, the numbers had vastly increased. At its peak, in 1813, the regular army contained over 250,000 men. The British infantry was "the only military force not to suffer a major reverse at the hands of Napoleonic France."

In 1793, shortly before Britain became involved in the French Revolutionary Wars, the army consisted of three regiments of Household Cavalry, 27 line regiments of cavalry, seven battalions in three regiments of Foot Guards and 81 battalions in 77 numbered regiments of line infantry, with two colonial corps (one in New South Wales and one in Canada). There were 36 Independent Companies of Invalids, known by their Captain's name, scattered in garrisons and forts across Great Britain.

Administered separately by the Board of Ordnance, the artillery had 40 companies in four battalions of Foot Artillery, 10 companies in the Invalid Battalion, two independent companies in India and a Company of Cadets. Two troops of the Royal Horse Artillery were being organised. The Corps of Royal Engineers and Invalid Corps of Royal Engineers were specialised bodies of officers. The Corps of Royal Military Artificers consisted of six companies. There were also two Independent Companies of Artificers.

There was no formal command structure, and a variety of government departments controlled army units depending on where they were stationed; troops in Ireland were controlled by the Irish Establishment, rather than the War Office in London, for example. In 1793, the first steps towards formal organisation were taken when fifteen general officers were appointed to command military districts in England and Wales.

During the later part of the 18th century Britain was divided into three recruiting areas—with England and Wales generally called South Britain—which were further divided into Districts with their own Headquarters. Ireland had separate Districts and organisation, and Scotland, or North Britain, was one administrative area. Home defence, enforcement of law and maintenance of order was primarily the responsibility of the Militia, the Royal Veteran Battalions, the Yeomanry and the Fencibles. Another structure of Recruiting Districts and Sub-Divisions existed alongside this.

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Wikipedia