The eldest son and heir of a prominent and wealthy Essex family, Barrington was brought up with a strongly puritan outlook. Although not listed as an alumnus, he studied at Cambridge before entering Gray’s Inn. A serious youth, prone to bouts of depression, he collected books on a wide variety of subjects, including religion, law, history and travel.
Barrington’s father, serving as Essex’s senior knight of the shire, was a prominent figure in every Parliament of the 1620s, and may have encouraged his son to stand for Newtown in the Isle of Wight. Barrington was returned to the third Jacobean Parliament with the help of his brother-in-law (Sir) William Meux*, who lived on the island and managed the Barrington properties there. Among Barrington’s surviving correspondence is a summary of the opening proceedings and business of the first week of the session. From this it would seem that Barrington initially intended to compile a brief record of the Parliament’s proceedings. However, at some point he decided to keep as full a diary as possible which, in its surviving form, commences on 17 Apr. and ends on 27 November. Barrington may also have intended to supplement his account with material he gathered elsewhere, as his papers also include separate items, not in his hand, detailing speeches addressed to and made by the king during the Parliament.
Barrington’s first appointment of the Parliament, and one which indicates that he shared his father’s religious concerns, was to attend a conference with the Lords on the petition against recusants (15 Feb. 1621).
Barrington’s diary is unusual in that it includes notes of committees that its author attended, as well as debates on the floor of the Commons. Barrington had not been formally appointed to some of these bodies, such as the sub-committees of the grand committee for grievances concerned with the East India Company (19 Apr.), the licensing of alehouses (25 Apr.), and the authorization of fees taken by the masters in Chancery (27 April).
Barrington, recently widowed, did not stand at the 1624 general election, but helped to secure the return of his brother-in-law (Sir) Gilbert Gerard* at Newtown. Gerard wanted the seat in case he was defeated in the Middlesex shire election, but in the event this proved unnecessary, and at the ensuing election Newtown returned Barrington as his replacement. It is not known whether Barrington continued his former practice of note-keeping; no diaries by him for this and subsequent parliaments appear to have survived. He played little recorded part in the 1624 assembly, but was among those ordered to consider legislation for collecting fines imposed on recusant wives (1 May 1624), to prepare for a conference with the Lords on Bishop Harsnett of Norwich, who had been accused of suppressing preachers (15 May), to attend another conference on expiring laws (22 May), and to present the grievances to the king on 28 May.
On the succession of Sir William Cavendish I* to the peerage in March 1626 Barrington, as one of the family trustees, was ordered by the Privy Council to help him order his estates, which were encumbered with debts, and to safeguard the deeds of his mortgaged properties from unscrupulous lenders.
In the wake of his father’s resistance to the Forced Loan and imprisonment, Barrington was removed from the Essex commission of the peace but escaped further penalty, and was restored two years later.
On the opening of the new session Barrington was again appointed to the privileges committee (20 Mar. 1628), and six days later was chosen as one of the managers of a conference with the Lords to review the recusancy laws.
With the death of his father on 3 July 1628 Barrington succeeded to the baronetcy and to an estate conservatively estimated at £3,000 p.a.
Barrington’s interest in colonial expansion may have been sparked by his involvement in the committees for the Somers Island petition, and he joined with some of the leaders of that enterprise, including his Essex neighbour Sir Nathaniel Rich*, to invest in the Providence Island Company in 1631. His participation in this puritan venture, along with his brother in law Gerrard, and other veterans of the Parliament such as John Pym and Benjamin Rudyard, brought Barrington into the circle of Charles I’s leading opponents during the Personal Rule. Barrington stayed in the Isle of Wight for a protracted visit in 1630-2, during which time he compiled various memoranda concerning his estates there and served on the local sewer commission.
