Infante Ferdinand, Count of Flanders

Infante Fernando of Portugal, Count of Flanders (pron. IPA2|fɨɾ'nɐ̃du; English Ferdinand; Old French Ferrand) was a Portuguese infante, fourth son of Portuguese King Sancho I and Dulce Berenguer. He was Count of Flanders by marriage to Jeanne of Flanders, eldest daughter of Baldwin IX of Flanders. Ferdinand was born on March 24 1188.

Ferdinand married Jeanne on January 1212 in Paris. He was the nephew of Jeanne's great-aunt-by-marriage Matilda of Portugal.

While on their way to Flanders the newlyweds were captured by Jeanne's first cousin Louis (the future Louis VIII of France), eldest son of Philip Augustus and Jeanne's aunt Elizabeth of Flanders. Louis' aim was to acquire his dead mother's dowry, a large piece of Flemish territory including Artois, which Jeanne's father had taken back by force after Elizabeth's death.

Released after this concession, Jeanne and Ferdinand soon joined the old allies of her father, king John of England and Emperor Otto IV, in an alliance against France. They were decisively defeated at Bouvines in July 1214, where Ferdinand was taken prisoner.

Ferdinand was to remain in French hands for the next 12 years, while Jeanne ruled alone.

He died in Noyon on July 27 1233.