The title Admiral of France is one of the Great Officers of the Crown of France, the naval equivalent of Marshal of France. The title was created in 1270 by Louis IX of France, during the Eighth Crusade. At the time it was equivalent to the office of Constable of France. The Admiral was responsible for defending the coasts of Picardy, Normandy, Aunis, and Saintonge. In times of war, it was his responsibility to assemble French merchant ships into a navy. He had to arm, equip, and supply the ships for the course of the war, and give letters of marque to corsairs. In peacetime, he was responsible for the maintenance of the royal fleet (when one existed). He was also responsible for maritime commerce and the merchant fleet.