Viscount FitzWilliam, of Merrion in the County of Dublin, was a title in the Peerage of Ireland

Peerage of Ireland

The Peerage of Ireland is the term used for those titles of nobility created by the English and later British monarchs of Ireland in their capacity as Lord or King of Ireland. The creation of such titles came to an end in the 19th century. The ranks of the Irish peerage are Duke, Marquess, Earl,...

. It was created in 1629 for Thomas FitzWilliam, along with the subsidiary title Baron FitzWilliam, of Thorncastle in the County of Dublin, also in the Peerage of Ireland. He was succeeded by his son, the second Viscount. In 1661 he was created Earl of Tyrconnell in the Peerage of Ireland. The earldom became extinct on his death in 1667 while he was succeeded in the barony and viscountcy by William FitzWilliam, the third Viscount. The fifth Viscount represented Fowey

Fowey (UK Parliament constituency)

Fowey was a rotten borough in Cornwall which returned two Members of Parliament to the House of Commons in the English and later British Parliament from 1571 to 1832, when it was abolished by the Great Reform Act.-History:...

 in the British Parliament. The sixth Viscount was a member of both the Irish and English Privy Councils. The seventh Viscount was a benefactor and musical antiquarian. The titles became extinct on the death of the ninth Viscount in 1833.

The family seat was Mount Merrion House

Mount Merrion

Mount Merrion is an area of Dublin, Ireland. It is roughly 7 kilometres south of the city centre. It is situated on and around a hill of the same name.-Location and access:...

, County Dublin

County Dublin

County Dublin is a county in Ireland. It is part of the Dublin Region and is also located in the province of Leinster. It is named after the city of Dublin which is the capital of Ireland. County Dublin was one of the first of the parts of Ireland to be shired by King John of England following the...

. The Viscounts FitzWilliams had no direct relationship with the Earls FitzWilliam

Earl FitzWilliam

Earl Fitzwilliam was a title in both the Peerage of Ireland and the Peerage of Great Britain held by the head of the Fitzwilliam family. This family claim descent from William the Conqueror. The Fitzwilliams acquired extensive holdings in South Yorkshire, largely through strategic alliances through...

.

Viscounts FitzWilliam (1629)

• Thomas FitzWilliam, 1st Viscount FitzWilliam (1581–1650)
• Oliver FitzWilliam, 1st Earl of Tyrconnell, 2nd Viscount Fitzwilliam
  Oliver FitzWilliam, 1st Earl of Tyrconnell
  Oliver FitzWilliam, 1st Earl of Tyrconnell was an Irish nobleman.His father was Thomas FitzWilliam, 1st Viscount FitzWilliam, who was born in 1581 and died 1665....
  
   (d. 1667) (created Earl of Tyrconnell in 1661)

Earls of Tyrconnell (1661)

• Oliver FitzWilliam, 1st Earl of Tyrconnell, 2nd Viscount Fitzwilliam
  Oliver FitzWilliam, 1st Earl of Tyrconnell
  Oliver FitzWilliam, 1st Earl of Tyrconnell was an Irish nobleman.His father was Thomas FitzWilliam, 1st Viscount FitzWilliam, who was born in 1581 and died 1665....
  
   (d. 1667)

Viscounts FitzWilliam (1629; Reverted)

• William FitzWilliam, 3rd Viscount FitzWilliam (d. 1670)
• Thomas FitzWilliam, 4th Viscount FitzWilliam (d. 1704)
• Richard FitzWilliam, 5th Viscount FitzWilliam
  Richard FitzWilliam, 5th Viscount FitzWilliam
  Richard FitzWilliam, 5th Viscount FitzWilliam PC was an Irish nobleman and politician. He succeeded to the Viscountcy of FitzWilliam in 1704, and became a member of the Irish Privy Council in 1715. He was elected Member of Parliament for Fowey in 1727, a seat he held until 1734.In 1711 he built...
  
   (1677–1743)
• Richard FitzWilliam, 6th Viscount FitzWilliam
  Richard FitzWilliam, 6th Viscount FitzWilliam
  Richard FitzWilliam, 6th Viscount FitzWilliam, KB, FRS was a Irish peer, and property developer.He lived with his father-in-law at Richmond Green.He moved back to Mount Merrion.He was buried at Donnybrook Cemetery....
  
   (1711–1776)
• Richard FitzWilliam, 7th Viscount FitzWilliam
  Richard FitzWilliam, 7th Viscount FitzWilliam
  Richard FitzWilliam, 7th Viscount FitzWilliam was an Irish Viscount in the FitzWilliam family who was a benefactor and musical antiquarian. He founded the Fitzwilliam Museum in Cambridge, England, with a bequest of his library and art collection on his death in 1816...
  
  (1745–1816)
• John FitzWilliam, 8th Viscount FitzWilliam (1752–1830)
• Thomas FitzWilliam, 9th Viscount FitzWilliam (1755–1833)