Field Marshal Frederick Rudolph Lambart, 10th Earl of Cavan, (16 October 1865 – 28 August 1946), known as Viscount Kilcoursie from 1887 until 1900, was a British Army officer and Chief of the Imperial General Staff. He served in the Second Boer War, led XIV Corps during the First World War, and later advised the Government on the implementation of the Geddes report, which advocated a large reduction in defence expenditure; he presided over a major reduction in the size of the British Army. Early career Born into an aristocratic family of Anglo-Irish descent, he was the son of the 9th Earl of Cavan and Mary Sneade Lambart (née Olive). He was educated at Eton College, Christ Church, Oxford, and the Royal Military College, Sandhurst; Lambart was commissioned into the Grenadier Guards on 29 August 1885. He gained the courtesy title of Viscount Kilcoursie in 1887 when his father succeeded to the Earldom and was appointed Aide-de-Camp to the Governor General of Canada in 1891. He was promoted to captain on 16 October 1897, after he had been appointed regimental adjutant on 25 August 1897, a position he held until 17 March 1900. By then, the Grenadier Guards were involved in the Second Boer War in South Africa. He saw action as a company commander in the Battle of Biddulphsberg in May 1900, and, having succeeded to his father's titles on 14 July 1900, took part in operations against the Boers in 1901 and was mentioned in despatches. Following the end of the war in June 1902, he left Cape Town on the SS Sicilia and returned to Southampton in late July. After promotion to major on 28 October 1902, he became second-in-command of 2nd Battalion Grenadier Guards in July 1905. He was promoted again to lieutenant colonel and appointed Commanding Officer of 2nd Battalion Grenadier Guards on 14 February 1908. Appointed a Member of the Royal Victorian Order Fourth Class on 29 June 1910 and promoted to colonel on 4 October 1911, he retired from the British Army on 8 November 1913 and became Master of Foxhounds for the Hertfordshire Hunt. At that time he lived at Wheathampstead House in Wheathampstead. First World War He was recalled at the start of the First World War and was appointed commanding officer of the 4th (Guards) Brigade on 11 August 1914 and went on to lead the Brigade at the First