Holy Roman Empire central power had begun to decline following years of imperial adventures in Italian lands, often ceding hegemony in Western Europe to France, which had long since centralized power. France began an aggressive policy of expanding eastward, first to the rivers Rhône and Meuse, and when those borders were reached, aiming for the Rhine. In 1299, the French proposed a marriage alliance between Philip IV of France's sister Blanche and Albert I of Germany's son Rudolf, with Alsace to be the dowry; however, the deal never came off. In 1307, the town of Belfort was first chartered by the Counts of Montbéliard. During the next century, France was to be militarily shattered by the Hundred Years' War, which prevented for a time any further tendencies in this direction. After the conclusion of the war, France was again free to pursue its desire to reach the Rhine and in 1444 a French army appeared in Lorraine and Alsace. It took up winter quarters, demanded the submission of Metz and Strasbourg and launched an attack on Basel.
Who was successfully wed in 1299?