George Crespigny Brabazon Vivian, 4th Baron Vivian, DSO TD (21 January 1878 — 28 December 1940) was a British soldier from the Vivian family who served with distinction in both the Second Anglo-Boer War and World War I.
He was born at Connaught Place, London, on 21 January 1878 to Hussey Vivian, 3rd Baron Vivian and Louisa Duff.
He was educated at Eton College where he rowed in the VIII and was elected into Pop. Succeeding to the title in October 1893, at the age of 15, he took his seat in the House of Lords in February 1900. He subsequently joined the British Army and was commissioned a cavalry officer as second lieutenant in the 17th Lancers on 14 March 1900.
Lord Vivian served with considerable distinction in the Second Anglo-Boer War.
On 17 September 1901, Smuts' commando encountered the 17th Lancers in the vicinity of Tarkastad. Smuts realised that the Lancers' camp was their one opportunity to re-equip themselves with horses, food and clothing. A fierce fight, subsequently to be known as the Battle of Elands River took place with the Lancers being caught in a cross-fire and suffering heavy casualties. Stunned by the onslaught, the remaining Lancers put up a white flag. Deneys Reitz, a younger commando member, encountered Captain Victor Sandeman, the Lancers' commander, and Vivian, who was his lieutenant, among the wounded.