I Corps was an army corps in existence as an active formation in the British Army for most of the 80 years from its creation in the First World War until the end of the Cold War, longer than any other corps. It had a short-lived precursor during the Waterloo Campaign. It served as the operational component of the British Army of the Rhine during the Cold War, and was tasked with defending West Germany.
The 4th Infantry Division was a regular infantry division of the British Army with a very long history, seeing active service in the Peninsular War and Waterloo Campaign, the Crimean and Boer Wars and both World Wars. It was disbanded after the Second World War and reformed in the 1950s as an armoured formation before being disbanded and reformed again and finally disbanded on 1 January 2012.
The 5th Infantry Division was a regular army infantry division of the British Army. It was established by Arthur Wellesley, 1st Duke of Wellington for service in the Peninsular War, as part of the Anglo-Portuguese Army, and was active for most of the period since, including the First World War and the Second World War and was disbanded soon after. The division was reformed in 1995 as an administrative division covering Wales and the English regions of West Midlands, East Midlands and East. Its headquarters were in Shrewsbury. It was disbanded on 1 April 2012.
The Lancashire Fusiliers was a line infantry regiment of the British Army that saw distinguished service through many years and wars, including the Second Boer War, the First and Second World Wars, and had many different titles throughout its 280 years of existence. In 1968 the regiment was amalgamated with the other regiments of the Fusilier Brigade – the Royal Northumberland Fusiliers, Royal Warwickshire Fusiliers and the Royal Fusiliers – to form the current Royal Regiment of Fusiliers.
The 16th Infantry Brigade was an infantry brigade of the British Army that saw active service during the Second Boer War and the First and Second World Wars.
The 7th Light Mechanised Brigade Combat Team is a formation in the British Army with a direct lineage to 7th Armoured Brigade and a history that stretches back to the Napoleonic Wars. It saw active service in the Crimean War, the Second Boer War and both the First and the Second World Wars. In 2014, the 7th Armoured Brigade was re-designated as 7th Infantry Brigade, thereby ensuring that the famed "Desert Rats" continue in the British Army's Order of battle.
The 1st Armoured Infantry Brigade was an infantry brigade of the British Army with a long history including service during both the First and the Second World Wars. It was based at Tidworth Camp. Previously, it has been designated 1st (Guards) Brigade, 1st Infantry Brigade, 1st Mechanised Brigade, and under the initial Army 2020 reforms assumed the title of 1st Armoured Infantry Brigade. Under the Future Soldier programme, the brigade merged with the 1st Artillery Brigade to form the 1st Deep Recce Strike Brigade Combat Team.
The 18th Infantry Brigade was an infantry brigade of the British Army that saw active service during the First and the Second World Wars.
The 11th Security Force Assistance Brigade is a brigade of the British Army which is intended to train and assist foreign forces. In 2021, under the Future Army changes, the brigade was redesignated, formerly being the 11th Infantry Brigade & HQ South East. Prior to the Army 2020 changes in 2013, the brigade was temporarily activated for deployment to Afghanistan. Originally formed in the Second Boer War, the brigade was engaged during both World Wars.
The 19th Brigade is an Army Reserve formation of the British Army. As the 19th Infantry Brigade, it fought in the First and Second World War.
The 12th Armoured Brigade Combat Team, formerly the 12th Armoured Infantry Brigade, is a regular brigade of the British Army which has been in almost continuous existence since 1899 and now forms part of 3rd Division.
The 3rd Infantry Brigade was a Regular Army infantry brigade of the British Army, part of the 1st Infantry Division. Originally formed in 1809, during the Peninsular War, the brigade had a long history, seeing action in the Second Anglo-Afghan War, and during both the First and the Second World Wars.
The 10th Infantry Brigade was a Regular Army infantry brigade of the British Army formed during the Second Boer War in 5th Division, and during both World Wars the brigade was part of the 4th Infantry Division.
The 29th Infantry Brigade was an infantry brigade unit of the British Army. It was originally raised in 1914 and saw service during the First and Second World Wars and the Korean War.
The 8th Infantry Brigade was an infantry brigade of the British Army that saw active service in both the First and the Second World Wars, before being disbanded and reactivated in the 1960s. The brigade was finally being disbanded in 2006. It was formed before the First World War as part of the 3rd Division. As part of that division it spent the entire war on the Western Front from 1914 to 1918 in the First World War. The brigade was also active during the Second World War.
The 9th Infantry Brigade was a Regular Army infantry brigade of the British Army that saw active service during both the First and Second World Wars.
The 158th Infantry Brigade was an infantry brigade of the British Army that served in both the First and Second World Wars, before being disbanded in 1968. Throughout its existence the brigade was assigned to the 53rd (Welsh) Infantry Division and was composed almost entirely of Territorial battalions from the Royal Welch Fusiliers.
The 125th Brigade was an infantry brigade formation of the British Army that saw active service during both the First and Second World Wars. It was assigned to the 42nd Division and served in the Middle East and later in the trenches of the Western Front in the First World War. In the Second World War the brigade, now redesignated 125th Infantry Brigade, fought in Belgium and France before being evacuated at Dunkirk and was then converted into 10th Armoured Brigade.
The 197th Brigade was an infantry brigade formation of the British Army that saw distinguished active service in both the First and Second world wars.
The 113th Brigade was an infantry brigade formation of the British Army active in both the First and the Second World Wars.
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British Army 