The Blair family is of Celtic origin and is found early in Scotland. They were of the Presbyterian faith and moved from Scotland to the Province of Ulster in Ireland to avoid the attempt by the English to supplant the Presbyterian form of worship with that of the Church of England. Later, after harassment by the King's soldiers in Ireland, several families, including the Robert Blair family, emigrated to America on the ship Lady Sellerooke, arriving in Boston, MA in 1718.

We next hear of Robert Blair as being in Rutland, Worcester County, Massachusetts, in 1720. On 10 February 1726, he bought a farm in Worcester, MA, consisting of 62 acres from John Hubbard of Concord, MA, being "part of Joseph Marable's Second Division of the Common lands in Worcester, on and adjoined a hill west of Prospect Meadow and east of Halfway river."

Robert Blair was active in public matters, being a surveyor of highways in 1732 and one of a committee to "seat the meeting house" in 1735. Also, he served on a committee to settle and renew the boundaries between the north and south parts of Worcester, as well as to survey several pieces of common and undivided land on the south part of the town.

Robert and his wife, Isabella (Rankin) Blair had eleven children, those born before 1718 were born probably in Ireland. I have not found any records to indicate how many of the children came to America with the family.

• Matthew, b. ca. 1704/5.
• David, b. 1708/9.
• John, b. 1710.
• Sarah.
• Dolly.
• William, b. 1718.
• James.
• Robert, Jr., born in Rutland, MA 20 June 1720.
• Elizabeth, b. probably in Rutland, MA in 1724, bpt. in Sudbury, MA; m. (possibly) Oliver Watson.
• Mary, b. probably in Rutland, MA 1 April 1725, bpt. in Sudbury, MA; m. John Watson.
• Joseph, b. probably in Worcester, MA in 1727.

Joseph, the youngest son of Robert and Isabella Blair, remained home with his parents and, on 14 December 1751, his father gave him a deed to the 60 acres of land including the homestead lot with all the buildings, except one half the house and one half the barn which were reserved for the parents' occupancy.

Joseph and his wife, Mary (--) Blair had twelve children, all born in Worcester, MA:

• Charles, b. 3 April 1752.
• Isabel, b. 27 Dec. 1754.
• Robert, b. 26 March 1756; m. Betsey Harrington.
• Twins:
  • Increase, b. 24 May 1758.
  • Jarves, b. 24 May 1758.
• Mary, b. 6 Sept. 1760; m. Simeon Duncan.
• Sarah, b. 20 July 1762.
• Dorothy, b. 12 May 1765.
• Elizabeth, b. 1 July 1767.
• Hannah, b. 10 July 1769.
• Joseph, Jr., b. 21 March 1774; m. (1) Marcy Dickerson; m. (2) Clarissa Aldrich.
• Charles, b. 1 Sept. 1776.