Complex sentence: In 1776 Mount Stuart was elevated to the Peerage as Baron Cardiff, of Cardiff Castle in the County of Glamorgan, but continued to be known by his courtesy title of Lord Mount Stuart.
Split into simpler sentences: In 1776 Mount Stuart was elevated to the Peerage as Baron Cardiff, of Cardiff Castle in the County of Glamorgan. Though this title was also used, he continued to be sometimes to be known by his courtesy title of Lord Mount Stuart.