The son of an English father and a Russian mother, Walcot travelled through Europe with his parents, returning to Russia at the age of 17, to study Architecture under Benois at The Imperial Academy of Art, St. Petersburg. He also studied in Paris at The Ecole des Beaux-Arts and the Atelier Redon. He practised Architecture in Moscow for five years, designing the city's Hotel Metropole (1898), and subsequently visiting Rome and London. Settling in London in 1907, he was first employed as a draughtsman to South African born architect Eustace Frere. He soon became a freelance draughtsman, producing presentation drawings for architects to show their clients and to exhibit at The Royal Academy. He also showed watercolours and etchings with leading exhibiting societies, and was elected to the membership of the Royal Society of Painter-Etchers and Engravers (ARE 1918, RE.1920) and the Royal Society of British Artists (1913). He was additionally a Fellow of the Royal Institute of British Architects (1922) and an associate of the British School of Rome. The most celebrated architectural draughtsman in England through the nineteen-twenties and thirties, he worked from studios in London, Oxford and Rome at the height of his career.