Harington’s father, the brother of Sir James Harington*, served for many years in Ireland, probably with more honour than profit, and represented County Wicklow in the Irish Parliament in 1585. Following the deaths of his father and his elder half-brother, Harington succeeded to an estate encumbered with debt. He was further required to find portions of £500 for each of his four surviving sisters and annuities of £50 for his younger brothers. Perhaps intending to increase his income from his estates he attempted to enclose Bagworth manor, in Leicestershire, but his tenants opposed it leading to the further expense of litigation in Chancery.
Harington may have been motivated to stand for Parliament as a means to gain some respite from his creditors. Ahead of the elections to the third Jacobean Parliament in 1620 he and his brother-in-law Moryson were recommended to the corporation of Leicester by his cousin, the 5th earl of Huntingdon.
In May 1621 Harington obtained a reversion to Moryson’s post in the Ordnance.
Harington was again unsuccessful at Hertford in the general election of 1625, in a contest for the second seat.
