The title of Duke of Ireland was created in 1386 for Robert de Vere, 9th Earl of Oxford

Robert de Vere, Duke of Ireland

Robert de Vere, Duke of Ireland, Marquess of Dublin, and 9th Earl of Oxford KG was a favourite and court companion of King Richard II of England.-Royal favour:...

, the favourite of King Richard II

Richard II of England

Richard II was King of England, a member of the House of Plantagenet and the last of its main-line kings. He ruled from 1377 until he was deposed in 1399. Richard was a son of Edward, the Black Prince, and was born during the reign of his grandfather, Edward III...

 of England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

, who had previously been created Marquess of Dublin. Both titles were Life peerages. At this time, only the Pale

The Pale

The Pale or the English Pale , was the part of Ireland that was directly under the control of the English government in the late Middle Ages. It had reduced by the late 15th century to an area along the east coast stretching from Dalkey, south of Dublin, to the garrison town of Dundalk...

 of Ireland

Ireland

Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

 (the Lordship of Ireland

Lordship of Ireland

The Lordship of Ireland refers to that part of Ireland that was under the rule of the king of England, styled Lord of Ireland, between 1177 and 1541. It was created in the wake of the Norman invasion of Ireland in 1169–71 and was succeeded by the Kingdom of Ireland...

) was under English rule. Despite its name, the Dukedom of Ireland is generally considered to have been one in the Peerage of England

Peerage of England

The Peerage of England comprises all peerages created in the Kingdom of England before the Act of Union in 1707. In that year, the Peerages of England and Scotland were replaced by one Peerage of Great Britain....

, and is the first time that a Ducal title was created for someone who was not a close relative of the King.

The arms with three crowns that were granted to Duke Robert as an augmentation

Augmentation of Honour

In heraldry, an augmentation is a modification or addition to a coat of arms, typically given by a monarch as either a mere mark of favour, or a reward or recognition for some meritorious act...

 to his arms in 1386 continued to be used for nearly a century as the arms of the Lordship of Ireland

Coat of arms of Ireland

The arms of Ireland is blazoned as Azure a harp Or, stringed Argent . These arms have long been Ireland's heraldic emblem. References to them as being the arms of the king of Ireland can be found as early as the 13th century...

.

The Duke fell from favour shortly after receiving the title, which was forfeited in 1388. The title of "Duke of Ireland" was never used again.

Dukes of Ireland (1386)

also Marquess of Dublin (for life, 1385–1388), Earl of Oxford

Earl of Oxford

Earl of Oxford is a dormant title in the Peerage of England, held for several centuries by the de Vere family from 1141 until the death of the 20th earl in 1703. The Veres were also hereditary holders of the office of master or Lord Great Chamberlain from 1133 until the death of the 18th Earl in 1625...

 (1142–1388)

• Robert de Vere, Duke of Ireland
  Robert de Vere, Duke of Ireland
  Robert de Vere, Duke of Ireland, Marquess of Dublin, and 9th Earl of Oxford KG was a favourite and court companion of King Richard II of England.-Royal favour:...
  
   (d. 1392) forfeited his titles in 1388. Life Peerage.