The origins of the Eighty Years' War are complicated, and have been a source of disputes amongst historians for centuries. The Habsburg Netherlands emerged as a result of the territorial expansion of the Burgundian State in the 14th and 15th centuries. Upon extinction of the Burgundian State in 1477/82, these lands were inherited by the House of Habsburg, whose Charles V became both King of Spain and Holy Roman Emperor. While conquering and incorporating the rest of what would become the "Seventeen Provinces" during the Guelders Wars (1502–1543), and seeking to forge and centralise these disparate regions into one political entity, Charles aspired to counter the Protestant Reformation and keep all his subjects obedient to the Catholic Church.