The Dark Avenger

During the 14th century, the Hundred-Year War between France and England ends in a truce. The English army occupies French Aquitaine, but rebel French knights vow to continue the war and oust Prince Edward of Wales, English ruler of French Aquitaine. Prince Edward of Wales is the son of King Edward III of England and he also is the heir to the English throne. The rebel French knights resent his presence in French Aquitaine and they plot to kill the Prince. When their plot fails, they kidnap his consort, Lady Joan Holland. Desperate, Prince Edward rides to her aid disguised in black armor in order to conceal his identity. After a series of valiant adventures, Edward the Black Prince and his troops do one more climactic battle against the French rebel army. - IMDb