Rev Guy Wyndham Sich was born on 15 July 1898 in Chiswick, Middlesex, his father, Arthur, was 28 and his mother, Alexandra, was 22. He married Jean Denise Theobald in 1941 in Barnstaple, Devon. They had three children during their marriage. He died on 29 January 1958 at the age of 59.

Educated at Norland Place School, Notting Hill (1905-07); Rose Hill School, Banstead, Surrey (1907-11); Winchester College (1911-17); arrived in Cloister Time (Summer term) 1911 and left in 1917. He was in H or Trant’s House. His housemaster would have been GM Bell. He won prizes for Latin Speech, English Speech, French, and Reading.

On leaving Winchester in April 1917, he went for 4 months to the Household Brigade Officers' Cadet Battalion at the Hall, Bushey Heath, then was commissioned in the Special Reserve of the Grenadier Guards. He went to France on 9 March 1918 and was wounded in the right thigh by shrapnel on 12 April 1918 on the River Lys.

The Battle of the Lys (also known as the Lys Offensive, the Fourth Battle of Ypres, the Third Battle of Flanders (French: 3ème Bataille des Flandres) and as the Batalha de La Lys in Portugal) was part of the 1918 German offensive in Flanders during World War I (also known as the Spring Offensive). It was originally planned by General Ludendorff as Operation George but reduced to become Operation Georgette, with the objective of capturing Ypres and forcing the British forces back to the Channel ports (and thereby out of the war). The battle began on 7 April 1918, and lasted until 29 April. In planning, execution and effects, Georgette was similar to (although smaller than) Operation Michael, earlier in the Spring Offensive.

Listed in National Archive as WO 339/100989 and separate medal card reference of WO 372/18/61899 as Second Lieutenant. He was demobilised on 19 January 1919. He converted to Catholicism on 4 October 1919.

Magdalen College (1919-22) where he was a Demy and graduated with an Honours Degree (second class) in History.

From September 1922 to 1926 he studied theology at St Edmund's College, Old Hall, Ware and from 1926-1928 at the Procure de St Sulpice, Rome. Having been ordained to the priesthood on 17 July 1927 he was Assistant priest to Bishop Bidwell and afterwards Archbishop Goodier at St Mary's, Cadogan St, Chelsea, from Jan 1928.

1931-3 Headmaster Oratory School Caversham.

1934 Chaplain of Magisterial Obedience Order of Hosp. of St. John (address given as 36 Linacre Road, NW2). From 27 October 1937 served as a priest at Our Lady of Victories (just off Kensington High St) which was bombed during the Blitz.

Margaret Theobald was engaged to Hans Welser, an Austrian Catholic, and she took instruction in Catholicism from GWS who was invited back to Coleherne Court for tea where he met and fell in love with Jean Theobald (Margaret Welser's sister).

As his services as a priest in London were no longer required he went to stay with his parents in Croyde, Devon where Jean followed him. He was excommunicated in 1941 for marrying her on 6 March 1941 (honeymoon in Exeter, Devon), a penalty that was lifted some 10 years later.

1942 Cabinet secretariat then Foreign Office (Hans Welser helped him to get in).

Served in Rouen as Vice-Consul 1951-2 (Appointed 28 Aug 1951, London Gazette) and then returned to UK to work in the Foreign Office Library. Lived briefly in Queen's Gate Terrace SW7 then rented a maisonette at 30 Cornwall Gardens, SW7.

He was admitted to University College Hospital in late 1957 for an operation on his gall-bladder. He failed to take sufficient exercise following the operation and suffered a coronary thrombosis.