The later years of Norman rule over Malta brought massive waves of immigration to the Islands from Sicily and from the Italian mainland, including clergy and notaries. Sicilian became the sole written language of Malta, as evidenced by notarial deeds from this period, but this was eventually supplanted by Tuscan Italian, which became the primary literary language and the medium of legal and commercial transactions in Malta. A large number of Sicilian and Italian words were adopted into the local vernacular.