Mormaerdom of Caithness

The Mormaer of Caithness was a vassal title and a member of the Norwegian nobility since the Viking Age and until 1476.

The mormaerdom Caithness was intermittently held—presumably always as fief of Scotland— by the Norse Earls of Orkney, at least since the days of childhood of Thorfinn Sigurdsson in c. 1020, but possibly already several decades before. The modern reconstruction of holders of peerage earldoms do not usually include those of Caithness, although there is no essential difference between them and, for example, those of Mormaers of Lennox, Mormaers of Strathearn and Mormaers of Angus.

In 1334 the then Earl of Orkney, who was still a Norwegian vassal, was created or recognized as Earl of Caithness (see there for how the mormaerdom of Caithness continued as an earldom). In the true circumstances of 14th century this presumably was just a recognition of his hereditary right to the ancient earldom/mormaership of Caithness. Next year, all his Scottish titles were forfeited for treason. The next grant after Earl Malise's confiscation was to David Stewart, a younger son of King Robert II of Scotland.

The list is by necessity a fragmentary one, archives being not fully preserved, actual reign of some supposed mormaers being not fully attested, and so forth:

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