In the High Middle Ages, France was a powerful but highly decentralized feudal kingdom in which the king's authority was barely felt. King Philip Augustus achieved remarkable success in the strengthening of royal power and the expansion of his realm, defeating his rivals and doubling its size. By the end of his reign, the kingdom had emerged as the most powerful state in Europe. From the mid-14th to the mid-15th century, France was plunged into a series of dynastic conflicts for the French throne, collectively known as the Hundred Years' War, and a distinct French identity emerged as a result. The French Renaissance saw art and culture flourish, various wars with rival powers, and the establishment of a global colonial empire, which by the 20th century would become the second largest in the world. The second half of the 16th century was dominated by religious civil wars between Catholics and Huguenots that severely weakened the country. But France once again emerged as Europe's dominant cultural, political, and military power in the 17th century under Louis XIV following the Thirty Years' War. An inadequate taxation system, coupled with defeat in the Seven Years' War and costly involvement in the American War of Independence, left the kingdom in a precarious economic situation by the end of the 18th century. This precipitated the French Revolution of 1789, which overthrew the absolute monarchy, replaced the "" with one of history's first modern republics, and produced the Declaration of the Rights of Man and of the Citizen, which expresses the nation's ideals to this day.