John I of Dreux (in French Jean I de Dreux) (1217–October 8 1286), known as "the Red" (le Roux) due to the colour of his beard, was Duke of Brittany, from 1237 to his death. He was son of Duke Peter I and Alix of Thouars, heiress of the duchy. In 1236 John married Princess Blanche of Navarre, daughter of Theobald IV of Champagne.

John was nominal duke from 1221, date of his mother’s death, although his father ruled as regent until he reached adulthood.

See also

• Dukes of Brittany family tree