In 481 CE, the Salian Franks crowned Clovis I their king. At the age of fifteen, the young monarch set about uniting all the Franks barbarian tribes that inhabited much of the region that became modern-day France and Germany. A fierce warrior and an astute administrator, he expanded his originally modest kingdom in northeast Gaul (France) by all possible means, including conquest, marriage, diplomacy, and deception. When he married Clotilda, a devout Roman Catholic, he converted to Catholicism and became instrumental in spreading his new religion across Europe. By the time Clovis died in 511, his domain covered most of Western Europe, from the North Sea to the Mediterranean, and from the Atlantic Ocean to the source of the Danube River. The French regard him as the founder of their monarchy.