John III the Good was Duke of Brittany, from 1312 to his death and 5th Earl of Richmond from 1334 to his death. He was the son of Arthur II, Duke of Brittany, and his first wife Marie, Viscountess of Limoges. John was strongly opposed to his father's second marriage to Yolande and attempted to contest its legality.

From Wikipedia (CC BY-SA 4.0).

Key facts

Born: March 8, 1286
Died: April 30, 1341

On IJR

No public IJR answers mention John III, Duke of Brittany yet. As people ask about it and share their answers, they'll appear here.

Facts from Wikidata (CC0). Image via Wikimedia Commons (Public domain).

Overview

From Wikipedia (CC BY-SA 4.0).