Norman Yoke
Very rare1.0%Starting as William in 1066, win the Invasion, become English, and have only English vassals
Be pedantic with this one - the conditions are stricter than they read. As William in 1066: win the Invasion, move your capital into de jure England to unlock the Embrace English Culture decision, and take it. Then the fiddly bit: every DIRECT vassal holding a county or duchy in de jure England must be English - revoke non-English dukes, transfer non-English counts under an English duke (keep at least one English duke to transfer to), and don't overlook stray direct vassals like landed bishops; more than one player has been blocked by a single forgotten bishopric. Players also report it should be completed as William himself, not a descendant, so don't dawdle across successions.