Passage: In the last few centuries, French strategic thinking has sometimes been driven by the need to attain or preserve the so-called "natural frontiers," which are the Pyrenees to the southwest, the Alps to the southeast, and the Rhine River to the east.[2] Starting with Clovis, 1,500 years of warfare and diplomacy has witnessed the accomplishment of most of these objectives. Warfare with other European powers was not always determined by these considerations, and often rulers of France extended their continental authority far beyond these barriers, most notably under Charlemagne, Louis XIV, and Napoleon.[3] These periods of incessant conflict were characterized by their own standards and conventions, but all required strong central leadership in order to permit the extension of French rule.[4] Important military rivalries in human history have come about as a result of conflict between French peoples and other European powers. Anglo-French rivalry, for prestige in Europe and around the world, continued for centuries, while the more recent Franco-German rivalry required two world wars to stabilize.[5]

Question: For approximately how long did the Anglo-French rivalry last?
centuries