On his missionary journey to Britain, he stopped to preach to the Celtiberians of northern Hispania.
Iria Flavia or simply Iria in Galicia, northwestern Spain, was a Celtiberian port, the main seat of the Caporos, on the road between Braga and Astorga.
Schulten led the 1905-12 excavations of the celtiberian city of Numantia and the Roman camps nearby and in 1924 searched without success for the location of Tartessos.
Archaeological findings have attested human presence in the area from the Bronze Age; the first historical inhabitants were the Lusitanians, followed by the Celts, who came from east to the Pyrenees.
It has roots going back to pre-Roman times, being developed by the Celtiberians who lived in the modern-day provinces of Ávila, Salamanca, and Zamora.
The first human settlements in the area date to the Neolithic age, while the first historically known people living here were the Celtiberians, who lived in Bergidum, later known as Bergidum Flavium after the Roman conquest.