George Colvin was born in Hampstead in London on 8 September 1911, the son of Ian Duncan Colvin and Jane Sophie Colvin (née Robson). He joined the Royal Navy as a Cadet at the Royal Naval College Dartmouth in May 1925. He passed out with four months seniority on 1 January 1929 and was appointed to the Battle Cruiser HMS RENOWN on 5 January 1929. He was promoted to Midshipman on 1 September 1929 and was appointed to the Cruiser HMS CUMBERLAND on 4 January 1930. On 31 December 1931 he joined the Royal Naval College, Greenwich for Lieutenant’s Courses and was promoted to Acting Sub Lieutenant on 16 May 1932. On 22 August 1932 he joined the Naval College at Portsmouth for his (G), (T) & (N) Courses.

He was appointed to the Submarine Flotilla Leader HMS MACKAY for Submarines on 16 September 1933 and was promoted to Lieutenant on 16th December 1933. In January 1935 he was serving in HMS L18 as Third Hand (Second Submarine Flotilla) to which he had been appointed on 15 April 1934. On 3 May 1935 he was serving in Submarine L69 as Third Hand and, on 9 January 1936, he joined HMS PIGMY for Reserve Group Submarines at Portsmouth. On 8 September 1936 he joined HMS L26 as the First Lieutenant. On 2 March 1937 he was appointed to the Submarine Depot Ship HMS MEDWAY (Fourth Submarine Flotilla) at Hong Kong and, in September 1937 he joined HMS PERSEUS as the First Lieutenant.

George Colvin returned home for his Commanding Officers Qualifying Course on 26 February 1940 and, having successfully completed the Course, he was appointed to Submarine H43 in Command on 15 April 1940 followed by HMS SUNFISH in Command on 18 September 1940. On 12 December 1940, while operating close to the Norwegian coast, SUNFISH torpedoed and sunk a German supply ship of about 4,010 tons. The enemy ship was deeply laden, and it is probable that she was carrying a large cargo of ore to Germany. Two torpedoes from SUNFISH were seen to hit, and the enemy ship broke up and sank immediately. SUNFISH also attacked a German oil tanker of about 4.000 tons. The ship was hit and damaged. In April 1941. in less than a week. SUNFISH sank three heavily laden supply ships off the Norwegian coast

On 31 August 1941 he was appointed to HMS GRAPH in Command (ex-German U-570) for the passage from Iceland to Barrow in Furness for a refit after her capture by the Royal Navy. He was promoted Lieutenant Commander on 16 December 1941. This was followed by an appointment to HMS SEALION in Command on 11 October 1941. He was appointed to HMS TIGRIS in Command on 15 April 1942. In December 1942 George Colvin conducted a torpedo attack in which the Italian Submarine Porfido was sunk.

HMS TIGRIS was lost with all hands on 27 February 1943. In the morning he was on patrol in the Mediterranean South-East of the Island of Capri. HMS TIGRIS was detected by the German Anti-Submarine Vessel UJ2210. A series of four depth charge attacks was made and the final one of these attacks brought wreckage and oil to the surface.

The submarine was declared officially lost on 10 March 1943 on failing to return to harbour.

For his services in Submarines George Colvin was Mentioned in Despatches on 3 September 1940, was awarded the DSC on 1 January 1943 and the DSO on 26 March 1943.

He is commemorated on the Portsmouth Naval war Memorial on Panel No 72 Column No 3.