This Member’s father was descended from a Scottish minor gentry family; but Fullerton’s background remains obscure until he graduated at Glasgow and became a schoolmaster in Ireland. As a fellow of Trinity College, Dublin, he was able to supplement his income by serving James VI as an intelligence agent.
After his marriage (somewhat late in life) to the widow of another Scottish favourite, Lord Bruce, Fullerton resided chiefly on her Hertfordshire estate in Abbots Langley until it was sold by her son in 1624.
Fullerton was returned to Charles’s first Parliament for St. Mawes, a duchy of Cornwall borough, probably with the assistance of his kinsman by marriage, William Coryton*, Pembroke’s vice-warden.
There was a renewed rumour in Scottish circles in the autumn that Buckingham intended to remove Fullerton, but his good friend the 1st earl of Leicester (Sir Robert Sidney†), ascertained that Fullerton remained ‘in the same grace with the king’ as before, and he continued to receive substantial favours, such as a lease of the former royal forest of Gillingham at a nominal rent.
Fullerton does not appear to have stood again, despite having a personal interest in a bill exhibited in the 1628 Parliament concerning his wife’s son-in-law, Sir William Cavendish I*.
