The series revolves around the history of England during the reign of Queen Elizabeth I (1558-1603) and is embodied by Miranda Richardson. Edmund, Lord Blackader, the grandson of the original Black Adder, coped with the situation he faced. This Lord regularly deals with the Queen, Lord Chamberlain Lord Melchite, who is his only rival and the Queen's demented former nanny Nursie.
Given the caliber of these performers, one might be tempted to put the show's renewed success down to that alone. But you also have to figure in the fact that Curtis was now writing with Ben Elton.
Ben Elton joined Richard Curtis on scripting duties for Blackadder II...the character was given a brain and the sharpest of tongues, and everything changed, allowing Rowan Atkinson to deliver one of the great comedy performances in the role.