The Siculo-Norman kings relied mostly on the local Sicilian population for the more important government and administrative positions. For the most part, initially Greek, Arabic and Latin were used as languages of administration while Norman was the language of the royal court. Significantly, immigrants from France, England, North Europe, Northern Italy and Campania arrived during this period and linguistically the island would eventually become Latinised, in terms of church it would become completely Roman Catholic, previously under the Byzantines it had been more Eastern Christian.