Leiston Abbey outside the town of Leiston, Suffolk, England, was a religious house of Canons Regular following the Premonstratensian rule, dedicated to St Mary. Founded in c. 1183 by Ranulf de Glanville, Chief Justiciar to King Henry II (1180-1189), it was originally built on a marshland isle near the sea, and was called "St Mary de Insula". Around 1363 the abbey suffered so much from flooding that a new site was chosen and it was rebuilt further inland for its patron, Robert de Ufford, 1st Earl of Suffolk (1298-1369). However, there was a great fire in c. 1379 and further rebuilding was necessary.