When Catherine died in exile in 1517 Henry succeeded her in her claim on Navarre, which was disputed by Ferdinand I king of Spain; and under the protection of Francis I of France he assumed the title of king.
After ineffectual conferences at Noyon in 1516 and at Montpellier in 1518, an active effort was made in 1521 to establish him in the de facto sovereignty; but the French troops which had seized the country were ultimately expelled by the Spaniards.
In 1525 Henry was taken prisoner at the battle of Pavia, but he contrived to escape, and in 1526 married Margaret, the sister of Francis I and widow of Charles, duke of Alençon. By her he was the father of Jeanne d'Albret (d. 1572), and was consequently the grandfather of Henry IV of France. Henry, who had some sympathy with the Huguenots, died at Pau on May 25 1555.