Warin was the younger son of Hubert de Munchensy, lord of Edwardstone in Suffolk.
[1] It is not clear who his mother was as his father married twice—first to a woman who was possibly an heiress to Godric, the dapifer of Henry I of England and second to Muriel, daughter of Piers de Valoignes.
[2] Around 1151 Warin witnessed the foundation charter of Old Buckenham Priory with his brother Hubert.
[1] Warin married Agnes, daughter of Pain fitzJohn and his wife Sybil.
[3] Warin died either in 1162 or before that, as his widow was married to Haldenald de Bidun in that year.