The Urnfield culture might have brought proto-Italic people from among the Italo-Celtic tribes who remained in Hungary into Italy. These tribes are thought to have penetrated Italy from the east during the late second millennium BC through the Proto-Villanovan culture. They later crossed the Apennine Mountains and settled central Italy, including Latium. Before 1000 BCE several Italic tribes had probably entered Italy. These divided into various groups and gradually came to occupy central Italy and southern Italy. This period was characterized by widespread upheaval in the Mediterranean, including the emergence of the Sea Peoples and the Late Bronze Age collapse.