Quote Originally Posted by MacMillan of Rathdown View Post
When, in the fullness of time, HRH Prince Philip is laid to rest, Prince Edward will become the next Duke of Edinburgh, at which time he will undoubtedly take a more active interest in all things Scottish. Including, no doubt, trout fishing.
Although that is currently the announced plan, it is not by any means a given.

Prince Charles, as Prince Philip's eldest son, will inherit the title. When Charles becomes King the title Edinburgh will merge in the Crown. It will be up to Charles or his heir William to issue Letters Patent to create a second Duke of Edinburgh for Edward. The alternative is that Charles refuses and Edinburgh becomes one of the subsidiary titles of the Heir Apparent.