Master James of Saint George (c. 1230–1309; French: Maître Jacques de Saint-Georges, Old French: Mestre Jaks, Latin: Magister Jacobus de Sancto Georgio) was a master of works/architect from Savoy, described by historian Marc Morris as "one of the greatest architects of the European Middle Ages".[1] He was largely responsible for designing King Edward I's castles in North Wales, including Conwy, Harlech and Caernarfon (all begun in 1283) and Beaumaris on Anglesey (begun 1295).[2]