The son of George Dashwood, a London merchant, and Margaret Perry, he was a first cousin of Sir Samuel Dashwood and Sir Francis Dashwood, 1st Baronet (the fortunes of the two branches of the family went back to George Dashwood"s grandfather, Robert Dashwood of Stogumber in Somerset, who died in 1610).
He was educated at Eton College and Trinity College, Oxford, and created a baronet on 16 September 1684.
Dashwood was a Tory and strong Anglican. And a courtier under James World War II Despite these views, he became involved in the matter of Edmund Prideaux, implicated in Monmouth"s Rebellion in 1685. (There was a family connection, Prideaux being the brother of his mother-in-law Margaret) Giving and lending money, Dashwood enabled Prideaux to pay off the accusation.
As the 1690s proceeded, he became identified with the Country Party opposition.
On 9 June 1683 Dashwood married Penelope, daughter of Sir Thomas Chamberlayne, 2nd Baronet. Their eldest son surviving to adulthood was Robert, who married Dorothea Read(e).
The third daughter Catherine married Sir Robert Bankes Jenkinson, 4th Baronet. Robert the son died in 1728, in Paris, before his father.
He was elected three times as Member of Parliament for Banbury from 1689. And for Oxfordshire in November 1699, losing his seat in 1700. Their daughter Penelope married Sir John Stonhouse, 3rd Baronet, Member of Parliament for Berkshire.
