| Who is it? | Medieval Breton Leaders |
| Birth Year | 1319 |
| Birth Place | French |
| Age | 700 YEARS OLD |
| Died On | Auray |
| Reign | 30 April 1341 – 29 September 1364 |
| Predecessor | John III |
| Successor | John IV |
| Spouse | Joanna, Duchess of Brittany |
| Issue | John I of Blois-Châtillon Guy Henry Marie, Lady of Guise Margaret, Countess of Angoulême |
| House | House of Blois |
| Father | Guy I of Blois-Châtillon |
| Mother | Margaret of Valois |
| Venerated in | Roman Catholicism |
| Beatified | 1904 by Pope Pius X |
| Canonized | 1364 (annulled) by Pope Urban V |
| Feast | 29 September (General Roman Calendar) |
| Patronage | -Army soldiers -Agricultural workers |
Charles I, Duke of Brittany, a prominent figure in medieval Breton history, is believed to have a net worth between $100,000 to $1 million in 2024. As one of the influential leaders in French medieval politics, Charles I held considerable power and wealth during his time. Being a duke brought him a vast landholding, numerous castles, and significant financial resources. His net worth estimate reflects the value of his inherited possessions, investments, and other lucrative ventures throughout his reign. Charles I, Duke of Brittany, left an indelible mark on Breton history, and his financial prowess only further solidifies his impact on the region's medieval landscape.
Subsequently, in 1904, Charles de Châtillon was beatified and therefore may be referred to as the Blessed Charles of Blois. His Roman Catholic Feast Day is 30 September.
