[2] Erskine was the third, but eldest surviving son of Sir Charles Erskine of Alva and Cambuskenneth, and his wife Mary Hope, daughter of Sir Thomas Hope, 1st Baronet of Craighall.
He succeeded his father as laird of Alva House on 8 July 1663 and purchased a baronetcy in Nova Scotia on 30 April 1666.
[3] Very few of the Nova Scotia baronets visited their lands, and the exercise was largely a money-raising exercise on the part of the Scottish Parliament, creating a new wave of baronets in the New World.
[4] Erskine was returned as Shire Commissioner for Clackmannanshire to the Conventions in 1665 and in 1667.
His daughter Helen Erskine (-1724) married John Haldane (1660-1721), 14th baronet of Gleneagles[6] His grandchildren included James Erskine, Lord Alva.