Marshal of France, born at Périgord; served bravely under Henry IV.; though a Catholic, favoured the Huguenots; narrowly escaped at the Massacre of St. Bartholomew; was killed at the siege of Épernay; carried a note-book with him everywhere, and so observant was he that it passed into proverb, "You will find it in Biron's note-book" (1524-1592).