Viscount Brouncker, of Lyons in the Province of Leinster, 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 on 12 September 1645 for the courtier Sir William Brouncker. He was made Baron Brouncker, of Newcastle in the Province of Munster, at the same time, also in the Peerage of Ireland. He was succeeded by his eldest son, the second Viscount. He was a distinguished mathematician and also held political office. He was unmarried and was succeeded by his younger brother, the third Viscount. He served as Cofferer of the Household

Cofferer of the Household

The Cofferer of the Household was formerly an office in the English and British Royal Household.The holder had special charge over other officers of the household and was an officer of state and a member of the Privy Council and the Board of Green Cloth....

 between 1680 and 1685. He was childless and the titles became extinct on his death in 1688.

Sir Henry Brouncker (d. 1607), father of the first Viscount, was Lord President of Munster.

Viscounts Brouncker (1645)

• William Brouncker, 1st Viscount Brouncker (1585–1645)
• William Brouncker, 2nd Viscount Brouncker
  William Brouncker, 2nd Viscount Brouncker
  William Brouncker, 2nd Viscount Brouncker, PRS was an English mathematician.Brouncker obtained a DM at the University of Oxford in 1647. He was one of the founders and the first President of the Royal Society. In 1662, he became Chancellor to Queen Catherine, then chief of the Saint Catherine's...
  
   (1620–1684)
• Henry Brouncker, 3rd Viscount Brouncker (1626–1688)