 Ricberht was replaced by Sigeberht, whose Christian education ensured that Christianity was reestablished.During Sigeberht's joint reign with Ecgric, the East Anglian see at Dommoc was established.During 632 or 633, Edwin of Northumbria was overthrown and slain and his kingdom was ravaged by Cadwallon ap Cadfan, supported by Penda of Mercia.