The earldom of Arran currently exists in two forms within the Scottish nobility. One is a peerage title in the Peerage of Scotland, held as a subsidiary title by the Duke of Hamilton. The other is a baronage title in the Baronage of Scotland, currently held by Susan Clark Livingston, Countess of Arran (in her own right).^[1][2]

These titles and the title of Earl of Arran in the Peerage of Ireland should not be conflated, as they are separate and distinct. The Scottish earldoms refer to the Isle of Arran off the coast of Ayrshire, while the Irish title is held by the unrelated Gore family and pertains to the Aran Islands offshore from County Galway.

The baronage earldom of Arran supposedly originated during feudal times, with its caput at the ruined Lochranza Castle.^[4] In 1994, Lady Jean Fforde, who was the Countess of Arran at the time, disponed the earldom together with the castle to an anonymous successor.^[5][6]

Historically, the earldom was also held by the Duke of Hamilton, similar to the peerage title. However, in 1995, when Swiss businessman Willi Ernst Sturzenegger purchased Lochranza Castle, acquiring the associated feudal lands that had been sold outside the Hamilton family, this transfer of property also included disposition of the baronage earldom. According to Scots property law, this resulted in the succession of the baronage title passing to Sturzenegger, establishing its line of succession down to the present day.

In 1997, Sturzenegger petitioned the Lord Lyon King of Arms, seeking official recognition as "Willi Ernst Sturzenegger of Arran, Earl of Arran in the territorial baronage of Scotland". He also requested a grant of arms reflecting his claimed title as "Earl of Arran in the territorial baronage of Scotland". Sturzenegger based his petition on his assertion that he owned "the Lands and Earldom of Arran in the County of Bute including inter alia the Castle of Lochranza the caput thereof". In 2006, he further petitioned the Lyon Court, this time seeking official recognition as "Willi Ernst Sturzenegger of Arran, Feudal Earl of Arran" along with the appropriate heraldic additaments to represent this title. However, in his 2009 ruling, the Lord Lyon denied this second petition from Sturzenegger.^[7]

The arms of the baronage earldom of Arran are: Argent, a lymphad with the sails furled proper flagged gules. These are quartered today with the arms of Hamilton (Gules, three cinquefoils ermine) by the Duke of Hamilton.^[8] In a similar fashion the arms of the feudal Earldom of Orkney are quartered by the present Earl of Caithness, the arms of the feudal Barony (or Earldom) of Lorne are now quartered by the Duke of Argyll, and the arms of the feudal Lord of the Isles are quartered with Clan Stewart by the Duke of Rothesay, all in the form of Lymphads.

The peerage earldom was first created in 1467 in the Peerage of Scotland for Thomas Boyd. However, Boyd was later attainted for treason in 1469, and the title was forfeited.

The title was then recreated in 1503 for James Hamilton, 2nd Lord Hamilton. James Hamilton's grandson, also named James Hamilton, became the 3rd Earl of Arran. However, he was declared insane in 1562, and the title then passed to the king's favorite, Captain James Stewart, in 1581.

In 1609, the title passed to James Hamilton, 2nd Marquess of Hamilton, when he inherited the earldom. Then in 1643, the 3rd Marquess of Hamilton was made Duke of Hamilton and received a second grant of the earldom of Arran. This created two separate creations of the earldom of Arran within the Hamilton family.

When the 2nd Duke of Hamilton died, the 1503 creation of the earldom became dormant, as it was left unclaimed. Meanwhile, the 1643 creation of the earldom continued to descend with the Dukedom of Hamilton, and the two titles remain united to this day.

• Thomas Boyd, 1st Earl of Arran (died c. 1472) (forfeit 1469)

• Lady Jean Fforde, Countess of Arran (died 2017) (dispone 1994)
• Willi Ernst Sturzenegger, Earl of Arran (1995–2023)
• Susan Clark Livingston, Countess of Arran (2023–present)

• Kidd, Charles, Williamson, David (editors). Debrett's Peerage and Baronetage (1990 edition). New York: St Martin's Press, 1990, ^{[page needed]}
• Leigh Rayment's Peerage Pages ^{[self-published source] [better source needed]}