In 1488 Duke Francis II of Brittany died from a fall from his horse, leaving the Ducal throne to his daughter Anne. Anne would be forces to marry King Charles VIII of France, thus ending Brittany's independence. So what if Francis II lived longer? Would he remarry and successfully have a son? Would Anne be able to marry someone who would be able to preserve Brittany's independence?
What about Charles VIII and France? Before marrying Anne of Brittany he was engaged to Margaret of Austria/Burgundy, daughter of Maximilian I. She brought as her dowry the counties of Burgundy, Artois and Charolais. These territories would later be taken back by the Austrians after the betrothal was broken. So how would these territories being French change things? Would Charles VIII focus more on France's western border, thus not starting the Italian Wars?