Tensions rose between the United Kingdom and France following an assassination attempt on Emperor Napoleon III in January 1858. It emerged that the would-be assassin, Felice Orsini had travelled to England to have the bombs used in the attack manufactured. 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.
On 12 May 1859 the Secretary of State for War, Jonathan Peel issued a circular letter to lord lieutenants of counties in England, Wales and Scotland, authorising the formation of volunteer rifle corps and of artillery corps in defended coastal towns.
On 23 July 1859 a meeting was convened by the Lord Mayor of London with the aim of establishing a rifle volunteer corps in the City. The corps was duly formed and accepted into service as the 1st London (City of London Volunteer Rifle Brigade) Rifle Volunteer Corps on 14 December 1859. In 1881 the corps was affiliated to the King's Royal Rifle Corps (KRRC) as a volunteer battalion. In 1891 the unit's title was varied to 1st London Volunteer Rifle Corps (City of London Volunteer Rifle Brigade).During the Second Anglo-Boer War they provided Active Service Companies as reinforcements to the Royal Fusiliers, and were awarded the battle honour "South Africa 1900-'02". 
In 1908 reserve forces were reorganised with the creation of the Territorial Force. All rifle volunteer units within the County of London became battalions of the new London Regiment. The unit's title became the 5th (City of London) Battalion, The London Regiment (London Rifle Brigade).
First World WarEdit
With the outbreak of war in August 1914 the 5th Battalion was mobilised for service. At the same time additional recruits allowed a "second line" battalion: the 2/5th to be formed in September and the existing unit was redesignated as the 1/5th.   A "third line" duplicate, the 3/5th was formed in November 1914.   The 1/5th and 2/5th Battalions both fought on the Western Front with the 3/5th remaining in the United Kingdom and providing trained reinforcements.   All three battalions were disbanded at the end of the conflict in 1918/1919.
In 1920 the unit was reformed as part of the renamed Territorial Army (TA). In 1922 each of the battalions of the London Regiment was reconstituted as a separate regiment and accordingly they were renamed to 5th City of The Regiment (London Rifle Brigade). In 1924 the regiment was awarded eighteen battle honours for the 1914-1918 war. Of these it was permitted to display ten on its cap badge, shown below in bold type: 
- Ypres 1915 '17
- St. Julien
- Somme 1916 '18
- Albert 1916
- Le Transloy
- Arras 1917 '18
- Scarpe 1917 '18
- Langemarck 1917
- Menin Road
- Cambrai 1917
- Hindenburg Line
- Canal du Nord
- France and Flanders 1914-18
In 1937 there was a further reorganisation of the Territorial Army, with the various London Regiments redesignated as battalions of regular army regiments. The unit became: London Rifle Brigade, The Rifle Brigade (Prince Consort's Own). With the prospect of war with Germany becoming more and more likely the Territorial Army was doubled in size in 1939: the London Rifle Brigade was divided into 1st and 2nd Battalions. 
Second World WarEdit
The 1st LRB became a motorised unit and was redesignated as 7th Battalion, The Rifle Brigade in 1941. It served in North Africa and Italy.
The 2nd LRB was also renamed in 1941 as 8th Battalion, The Rifle Brigade. It served in North West Europe in 1944-1945.
- Bourguébus Ridge
- Mont Pincon
- Le Perier Ridge
- North-West Europe 1944-45
- Alam el Halfa
- El Alamein
- Tebaga Gap
- North Africa 1942-43
- Monte Malbe
- Gothic Line
- Argenta Gap
- Fossa Cembalina
- Italy 1944-45
Post-war and amalgamationEdit
At the end of the war all territorial units were disbanded. The TA was reformed in April 1947 and the London Rifle Brigade, The Rifle Brigade (Prince Consort's Own) was re-established as a single-battalion unit. 
In March 1950 it was announced that there was to be a reduction in the size of the TA, with a number of amalgamations to be carried out. Among the mergers was that of The London Rifle Brigade with The Rangers, another territorial battalion of the Rifle Brigade. The resulting unit, The London Rifle Brigade/Rangers was formed on 1 May 1950.
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 London Rifle Brigade. regiments.org.
- ↑ 7 RIFLES. British Army.
- ↑ War Office Circular, 12 May 1859, published in The Times, 13 May.
- ↑ 4.0 4.1 4.2 4.3 4.4 Short History of the London Rifle Brigade. Aldershot: Gale & Polden. 1916. http://ia600500.us.archive.org/13/items/londonrifle00regiuoft/londonrifle00regiuoft.pdf.
- ↑ 5.0 5.1 5.2 5.3 The London Regiment. The Long, Long Trail. The British Army in the Great War.
- ↑ "Battle Honours. London And Scottish Regiments". 13 March 1924. p. 11.
- ↑ Kipling, Arthur L; King, Hugh L (2006). Head-Dress Badges of the British Army. Volume Two. Naval & Military Press. p. 170. ISBN 1843425130.
- ↑ 8.0 8.1 8.2 8.3 Regimental History: London Rifle Brigade. Fovant Badges.
- ↑ "Battle Honours List. Honorary Distinction For T.A. Battalion". The Times: p. 112. 15 October 1957.
- ↑ "Territorial Army Mergers. 137 Major Units Involved". The Times: p. 3. 22 March 1950.
- ↑ The Times: p. 2. 6 November 1950.