Background
Blackett was the eldest surviving son of William Blackett and his wife Elizabeth Kirkley. His father was a merchant of Newcastle and owned extensive property including coal mines.
Blackett was the eldest surviving son of William Blackett and his wife Elizabeth Kirkley. His father was a merchant of Newcastle and owned extensive property including coal mines.
He was a Justice of the Peace for Northumberland and the North Riding of Yorkshire from 1677 and J.P, for Ripon from 1679. From 1679 to 1680, he was High Sheriff of Northumberland which was during the Popish Plot and he was active in levying fines on recusants. However he was probably an opponent of exclusion, because he stayed on the commissions of the peace in 1680.
He succeeded to the baronetcy on the death of his father in 1680.
As a Justice of the Peace in the North Riding he responded to the questions on the Test Acting and Penal Laws in February 1688 but he was removed from the commission of peace later in the year 1688. He became freeman of Ripon in September 1688 and was re-appointed Justice of the Peace for Northumberland and the North Riding in 1689.
He also became commissioner for assessment for Yorkshire West and North Riding and Northumberland. He demolished the old house on the Newby estate and in 1695 with the assistance of Sir Christopher Wren began building Newby Hall at a cost of £32,000, which remained the family seat until 1748.
He was elected Member of Parliament for Northumberland in 1698 and sat until 1700.
Blackett died at the age of 67 and was buried in Ripon Minster. She died without surviving issue.
Blackett became a member of the Merchant Adventurers" company of Newcastle-upon-Tyne in 1672. In 1684 he became a member of the Hostmen of Newcastle-upon-Tyne. Also in 1689, Blackett was elected Member of Parliament for Ripon for a year from 1689 to 1690.