Dexter Fortescue

From Harry Potter Wiki

Dexter Fortescue was a Headmaster of Hogwarts School of Witchcraft and Wizardry. Not much is known about his time at Hogwarts. His painting hangs in the Headmaster's office and has been known to comment occasionally on current events. In 1995, he roared his disapproval at Cornelius Fudge and Dolores Umbridge after hearing the corrupt method they had used to overhear Dumbledore's Army in the Hogshead pub by bribing Willy Widdershins to spy on them.

He may be related to Florean Fortescue, who ran an ice cream parlour in Diagon Alley.