The titles of Duke of Ireland was created in 1386 for Robert de Vere, 9th Earl of Oxford, the favorite of King Richard II of England who had previously been created Marquess of Dublin. Despite its name, the Dukedom of Ireland is generally considered to have been one in the Peerage of England, and is the first time that a Ducal title was created for someone who was not a close relative of the King. The Duke fell from favor shortly after receiving the title, which was forfeited in 1388.
It was introduced to England by Richard II, brother-in-law of the Margrave of Brandenburg, the honour being conferred upon Robert de Vere, Earl of Oxford, who became Marquess of Dublin in 1385.
The precedence between Dukes and Earls caused great offence to the Earls, and the patent was revoked in1386 in favor of the Dukedom of Ireland.
When John Beaufort, Marquess of Dorset, was attainted and the House of Commons appealed to Richard II for it's restoration, Beaufort begged the King not to restore this particular title "as the name of Marquess is a strange name in this realm."
A woman with the rank of marquess, or the wife of a marquess, is a marchioness.
On the 13 October 1386 the patent of this marquessate was recalled, Robert de Vere as was raised to Duke of Oxford.
John de Beaufort, Earl of Somerset, the second legitimate son of John of Gaunt, was raised to the second marquessate as Marquess of Somerset and Marquess of Dorset on in September 1397.