Clan MacAulay (, ), also spelt Macaulay or Macauley is a Scottish clan. The clan was historically centred on the lands of Ardincaple, which are today consumed by the little village of Rhu and burgh of Helensburgh in Argyll and Bute. The MacAulays of Ardincaple were located mainly in the traditional county of Dunbartonshire, which straddles the "Highland Line" between the Scottish Highlands and Lowlands. Clan MacAulay has been considered a "Highland clan" by writers and has been linked by various historians to the original Earls of Lennox and in later times to Clan Gregor. The MacAulays of Ardincaple, like Clan Gregor and several other clans, have traditionally been considered one of the seven clans which make up Siol Alpin. This group of clans were said to have claimed descent from Cináed mac Ailpín, King of the Picts, from whom later kings of Scotland traced their descent. The chiefs of Clan MacAulay were styled Laird of Ardincaple. Clan MacAulay dates, with certainty, to the 16th century. The clan was engaged in several feuds with neighbouring clans. However, the clan's fortunes declined in the 17th and 18th centuries. After the decline and fall of Clan MacAulay, which ended with the death of Aulay MacAulay in the mid-18th century, the clan became dormant. With the revival of interest in Scottish clans in the 20th century a movement was organised to revive Clan MacAulay. The modern organisation strove to unite the three unrelated groups of MacAulays, and all who bore the surname MacAulay, under one clan and chief. In 2002, the clan appointed a potential chief of Clan MacAulay, but his petition for formal recognition was denied by the Lord Lyon King of Arms. The Lord Lyon ruled that the petitioner did not meet two criteria: anyone without a blood link to a past chief must be Clan Commander for ten years before being considered for recognition, and that the chiefship in question was of the MacAulays of Ardincaple and not of all MacAulays. To date, Clan MacAulay does not have a chief recognised by the Lord Lyon King of Arms, and therefore can be considered an Armigerous clan. There are many different families of MacAulays from both Ireland and Scotland which are not related and are considered to have no historical connection with Clan MacAulay. These include the Scottish Macaulays from the Western Isles (the Macaulays of Lewis and possibly the MacAulays