Col. Sir William Cosby, Governor of New York

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William Alexander Cosby, Sir

Birthplace: Stradbally Hall, Queens County, Ireland
Death: Died in Fort George, New York, New York, United States
Cause of death: tuberculosis
Place of Burial: New York, NY, USA
Immediate Family:

Son of Alexander Cosby, Esq and Elizabeth Le' Estrange
Husband of Lady Grace Montagu
Father of Henry Cosby; Elizabeth Fitzroy-Jeffreys and Alexander Cosby
Brother of Alexander Cosby

Occupation: Soldier and Governor
Managed by: Private User
Last Updated:

About Col. Sir William Cosby, Governor of New York

General Notes:

Brigadier-General in the Army, Colonel of the Royal Irish

Colonel William Cosby arrived in New York City in August of 1732 to assume his duties as royal governor of the province of New York. Cosby had few qualifications to be governor. He secured his office by seeking it with desperate determination and by having the good luck to have married Grace Montague, a sister of the Duke of Halifax and a first cousin of the Duke of Newcastle, the British secretary of state and the guiding force in British colonial administration.

Cosby was a bad choice to represent the Crown in this pivotal, wealthy, and divided colony. Since 1664, when the Dutch colony of Nieuw Amsterdam surrendered to forces commanded by the Duke of York (later King James II), the renamed colony exhibited a staggering level of factional strife. Colonial New York's political history is a bewildering succession of truculent governors, conniving politicians, and contentious printers. Historians have identified a complex interplay of factional allegiance, focused on great and wealthy families, dividing by allegiance or opposition to the Crown, and complicated by religious and ethnic divisions; historians have also come to appreciate the seriousness of colonial political arguments and the sincerity with which contending sides espoused them.

Governor Cosby bears principal blame for the crisis into which he plunged New York. One reason was his hunger for money; he saw his governorship as a means to rebuild his shattered finances. New Yorkers soon had reason to dislike and distrust their new governor, who showed his determination to wring as much money out of his post as he could. Cosby made matters worse for himself with his contempt for those whom he was sent to govern, and his clumsy and arrogant interventions in the politics of colonial New York. He knew little and cared less about the structure of the colony's politics, and in particular the delicate truce between its two leading partisan alliances, one clustered around the Philipse and DeLancey families (who tended to support Crown authority) and the other allied with the Morris and Livingston families (who tended to defend local interests). Cosby openly courted the Philipse-DeLancey faction, offending and infuriating the Morrisites. Over a year of frenzied, bitter politicking left a stalemate in place by late 1733: The Morrisites controlled New York City and Westchester County; the rest of the colony either was neutral or leaned to the Cosby-Philipse-DeLancey alliance; and Cosby still controlled the colonial legislature, the governorship, and the judiciary.


Cosby, after the Zenger trial, did what he could to check the liberty of the citizens, but was soon stricken with a fatal illness. On his death-bed he called together the members of his council, and suspended his old enemy, Rip Van Dam, who would have been his successor until another Governor was appointed. And having done this he died, on March 10, 1736, leaving a quarrelsome state of affairs behind him. 123

bullet Research Notes:

Title info: NOTE Governor of New York

Refer to for full genealogical report - however there seems to be conflicting information in connection with William Cosby and his marriage to Lady Grace Montagu. This event is said to have taken place in 1711, but William's birth date is given as 1762. (new note 4/22/11: Please note amended birth year of 1690, supported by information provided in the wiki bio and by )

A wealth of information going back to the 1300's but needs verifying if this is your family.

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Col. Sir William Cosby, Governor of New York's Timeline

Queens County, Ireland
Age 27
London, Middlesex, England
Age 31
Age 31
March 10, 1736
Age 46
Fort George, New York, New York, United States
New York, New York
New York, NY, USA