The flag of the Isle of Man (Manx: brattagh Vannin) is a triskelion, composed of three armoured legs with golden spurs, upon a red background.

The last member of that ruling family died in 1265 without a legitimate heir, when the Isle passed into the possession of Alexander III, King of Scotland (d.1286).

The heraldic era in England and Scotland started in about 1215, slightly earlier in Western Europe, and members of the Crovan dynasty are known to have borne ships and lions on their seals,[3] and no evidence exists of their use of the triskeles.

[8] Henry invested considerable political capital in his son's new position, and in his efforts to raise funds from taxation to support the dignity of that kingship made himself extremely unpopular with his English nobles, who eventually rebelled.

[13] However, such usage of the flag was not sanctioned by the Board of Trade and the Admiralty under Section 105 of the 1854 Merchant Shipping Act in favour of the Red Ensign.

[13][14] This decision was reversed by the Admiralty on 4 March 1889 and Manx merchant ships were permitted to fly the Flag of the Isle of Man.