The name Norman derives from Northman, and as such is a reference to their Viking origins. They were initially a product of the Viking expansions that were occurring through much of the 800's. By 880, Vikings were colonizing Orkney, the Hebrides, Iceland, and parts of Ireland. Also by 880, they began arriving in what would become known as Normandy. By 911, they were so established that a treaty that year was reached with the Frankish King, Charles the Simple, that formally established the Duchy of Normandy. The Duchy was later expanded in 924 for continued loyalty to the, by now, French monarchy.