Sinclair Alexander-Sinclair was born in Malta, the second son of Captain John Hobhouse Inglis Alexander of the Royal Navy, who served as aide-de-camp to Queen Victoria, and Isabella Barbara Hume, daughter of Thomas Cochrane Hume. He succeeded his elder brother in the Southbar property in 1892 and two years later adopted the additional name of Sinclair on succeeding to the estate of Freswick in Caithness.[2]
Alexander-Sinclair entered the Royal Navy as cadet in 1879 at the age of 14, becoming a midshipman 2½ years later.[5] Edwyn Sinclair Alexander-Sinclair was first educated at Twyford School[6][7] He was made lieutenant in 1890,[8] and served as flag-lieutenant to both Admiral Tracey and Admiral Sir Michael Culme-Seymour,[8] gaining promotion to commander in January 1901.[7] He then had two sea commands, the destroyer Albatross from February 1902[9] serving at the Mediterranean Station from May that year; and after paying her off in January 1904, the despatch vessel Surprise until 1905.[7]
Soon afterwards, in December 1918, Alexander-Sinclair's 6th Squadron was sent to the Baltic, at the request of Estonian Government, to take part in the Estonian War of Independence. They delivered 6,500 rifles, 200 machine guns and two field guns. The British squadron also captured two Russian destroyers, Spartak and Avtroil, and turned them over to Estonia, which renamed them Vambola and Lennuk. Alexander-Sinclair then blockaded the Russian Navy base at Kronstadt[1] until relieved by the 1st Light Cruiser Squadron under Rear-Admiral Walter Cowan. He was Admiral-Superintendent of Portsmouth Dockyard from 1920 to 1922, and after promotion to vice admiral on 4 April 1922,[13] commanded the 1st Battle Squadron, Atlantic Fleet from 1922 to 1924. He then served as Commander-in-Chief, China Station from 1925 to 1926, and after promotion to admiral on 4 October 1926,[14] was Commander-in-Chief, The Nore from 1927 to 1930. He retired in 1930.[15]
