Lord Somerville is a title in the Peerage of Scotland which is subject to a number of ambiguities. The date of creation is not known with certainty but it was probably created about 1435 for Thomas Somerville, Justiciar of Scotland. The title was omitted in 1606 when an ordered list of the Scottish peerage was produced following the union of the Scottish and English crowns, and the title was not used during the 17th century. In 1723, however, the House of Lords ratified and acknowledged the title for James Somerville the 13th Lord. The consecutive numbers ascribed to the numerous Lords differ according to which authority is consulted. The list below uses the numbers favoured by Burkes Peerage.