Antoine de Bourbon, duke of Vendome, king of Navarre (1518-62) was a French nobleman who played a minor part in the Hapsburg-Valois Wars, before being killed at the siege of Rouen (First War of Religion).
Bourbon became governor of Picardy after his father's death in 1537. In the same year he took part in Montmorency's invasion of Savoy, in which Turin and Pinerolo were captured (Third Hapsburg-Valois War).
At the start of the Fourth Hapsburg-Valois War (1542-44) he commanded one of the three French armies that operated on the north-eastern borders. He captured Saint-Omer and Béthune, but setbacks elsewhere meant that these initial French campaigns ended in failure. Late in 1543 the French carried out another invasion of Luxembourg, triggering a direct response from the Emperor Charles V. Charles began a siege of Landrecies, but broke it off when Francis I arrived in the area with the main French royal army. Bourbon took part in this campaign.
In 1548 he married Jeanne d'Albret, the heiress to the kingdom of Navarre, and in 1555 he became titular king of Navarre, although most of his kingdom was in Spanish hands.
Antoine became a Protestant in about the mid 1550s, and his son Henry was raised in that religion (later becoming Henry IV of France). Antoine was involved in some of the early Huguenot plots in the period before the outbreak of the First War of Religion (1562-63). Late in 1560 Navarre and his brother Condé were summoned to court at Orleans. Condé was condemned to death, Navarre was only watched, but they were both saved by the death of Francis II on 5 December 1560.
Francis was succeeded by the ten-year old Charles IX. Normally Navarre would have been his regent, but just before Francis's death he had surrendered his rights to that title to Catherine de Medici, the Queen Mother. He was appointed lieutenant-general of France, and became a key figure in her government. By the end of 1561 he had returned to the Catholic fold, possibly after Spanish representatives suggested that he might be compensated for the loss of Navarre if he did so.
After the death of Francis II in 1560 he was appointed lieutenant-general of France. He returned to the Catholic fold to take up the post, and commanded the Royal army early in the First War of Religion (the Protestants were commanded by his brother Louis I de Bourbon, Prince of Condé). Antoine was mortally wounded during the siege of Rouen (August-October 1562), a major Huguenot centre. His young son Henry went on to become a key leader of the Huguenot cause, at first as something of a figurehead due to his age, but later as an active and very able commander, and eventually as king.