Original: In Scandinavia , it became obsolete in the Middle Ages and was replaced with duke ( hertig/hertug ) ; in later medieval Britain , it became the equivalent of the continental count ( in England in the earlier period , it was more akin to duke , while in Scotland it assimilated the concept of mormaer ) .
Simplified: In Scandinavia , it got out of use in the Middle Ages , whereas , in Britain , it became synonymous with the continental count .