At the Battle of Waterloo in June 1815, the regiment charged down the slope to support the Union Brigade of medium cavalry.

[1] It was stationed in India between 1857 and 1860 in response to the Indian Rebellion and in Ireland from 1865 to 1870, before fighting in the Second Anglo-Afghan War in the late 1870s.

[22] The regiment was deployed to South Africa for service in the Second Boer War in October 1899, and took part in the relief of Kimberley and the ensuing Battle of Paardeberg in February 1900.

Almost 530 officers and men left Cape Town aboard SS Lake Manitoba in September 1902, arriving at Bombay the following month and was then stationed at Ambala in Punjab.

[26] The 9th/12th Royal Lancers celebrated Mons/Moy Day annually, which commemorated the last occasions on which each predecessor regiment charged with lances.

[28] In January–February 1935 a provisional D squadron of the 12th Lancers with eight armoured cars served as a peacekeeping force in the Saar region.

[29] On 31 December B and C squadrons were sent again to Egypt with 29 armoured cars as a response to the Italian invasion of Abyssinia and strengthening garrisons in Libya.

By the end of 1936 the squadrons were returned to Britain, where the regiment was re-equipped with Morris Light Reconnaissance Cars.

[30][31] The 12th Lancers was an armoured car regiment equipped with the Morris CS9, in the 1940 campaign in France and Flanders, playing a key part in shielding the retreat to Dunkirk.

Subsequently, the regiment fought as divisional troops for the 1st Armoured Division at the Second Battle of El Alamein in October 1942[33] and then served as a corps-level reconnaissance unit in the Italian Campaign.