In traditional cultures of the Stone Age, Bronze Age, and hunter-gatherer societies the warfare was mostly 'endemic', long duration, low intensity, usually evolving into almost a ritualized form. By contrast, Europe had moved to 'sporadic' warfare in the Middle Ages due to the availability of professionally mercenary armies. When Italy was ransacked by French and Spanish Armies in the early 1500s, most Italian states were easily defeated by armies practicing sporadic-warfare. Aztec and other native peoples practiced an endemic system of warfare as well, and so were easily defeated by Spanish and Portuguese sporadic-warfare armies in the early 1500s.