Francis III was Dauphin of France and, after 1524, Duke of Brittany. Francis and his brother, Henry, were exchanged as hostages for their father, Francis I, who had been captured at the Battle of Pavia. They would be hostages for three years. Made duke of Brittany in 1532, this precipitated Brittany's integration with the Kingdom of France. Francis died 10 August 1536, possibly from tuberculosis.

Francis I was King of France from 1515 until his death in 1547. He was the son of Charles, Count of Angoulême, and Louise of Savoy. He succeeded his first cousin once removed and father-in-law Louis XII, who died without a legitimate son.