Note: In Roman antiquity, Italia referred to the Italian Peninsula from the Apennines in the north to the "boot" in the south. It was the core of the Roman Empire. Cisalpine Gaul, north of the Apennines, was added in 42 BCE. The islands of Sicily, Corsica, and Sardinia, as well as Raetia and part of Pannonia to the north were included by the late 3rd century CE. The emperor Augustus divided Italy into 11 regions for administrative purposes.