Coenwulf may also have been behind the coup in 806 that led to Eardwulf losing his throne, and he likely continued to support Eardwulf's enemies after Eardwulf returned in 808.
Coenwulf tamén puido estar detrás do golpe do 806 que levou a Eardwulf a perder o seu trono, e igualmente continuou apoiando aos inimigos de Eardwulf despois do seu regreso no 808.