Who is the Chief of the Wizard's Council?

Answer 1

From Harry Potter Wiki:

The Wizards' Council was the predecessor to theMinistry of Magic, and governed the wizarding community of Great Britain until the formation of the Ministry.

The last Chief was Elfrida Clagg who served either in the fourteenth or seventeenth century.

Answer 2

The title is Chief Warlock of the Wizengamot. Albus Dumbledore is this Chief Warlock for most the series. It is unknown who the title was given to after his death and during his brief expulsion in the fifth novel.

Answer 3

Albus Dumbledore was the Chief Warlock of the Wizengamot for most of the series. He was briefing suspended in 1995-1996 but reinstated until his death in June 1997. It is unknown who took over the role.

Answer 4

Try 'Archimage' in any good Dictionary