Riwallon was the son of unknown parents. The date and place of his birth have not been found.
His wife was Gwenargent de Rennes. They were married, but the date and place have not been found. Their only known child was Tristan I (c1015-c1056).
| Attribute | Date | Description | Details | Source | Multimedia | Notes |
|---|---|---|---|---|---|---|
| Nobility Title | FROM 1008 TO 1040 | baron de Vitré |