It was first created as Earl of Cromarty in the Peerage of Scotland in 1703 for Sir George Mackenzie, 2nd Baronet, but his titles were forfeited after the Jacobite rising of 1745.

Sir Roderick's son, John Mackenzie, was in 1628 created a baronet, of Tarbat in the County of Ross, in the Baronetage of Nova Scotia, with remainder to his heirs male whatsoever.

He supported the Jacobite rising of 1745 and led a force of 400 men from Clan Mackenzie at the Battle of Falkirk in 1746.

[2] His eldest son and heir apparent, John Mackenzie, Lord MacLeod, fought alongside his father in the rebellion of 1745.

He achieved the rank of Major-General in the British Army, and was created a Count in the Swedish nobility, a title which was recognized by George II.

Lady Cromartie was succeeded according to the special remainder by her second surviving son, Lord Francis, the second Earl.

As Viscount Tarbat he had been sub-lieutenant in the Shropshire Yeomanry in 1876[4] and was later a Major in the 2nd Volunteer Battalion of the Seaforth Highlanders and served as a Vice-Lord-Lieutenant and Deputy Lieutenant of Ross and Cromarty.

In 1979, he discontinued the use of the surname Blunt for himself and his son and was recognized by the Lord Lyon as Cabarfeidh[5] (Chief) of Clan Mackenzie.

The heir apparent is the present holder's son Colin Ruaridh Mackenzie, Viscount Tarbat (born 1987).