The Sackvilles, originally from Sauqueville in Normandy, acquired Buckhurst in the parish of Withyham in East Sussex in the twelfth century, and first produced a knight of the shire in 1361.
Sackville’s father, ennobled in 1567, became lord treasurer in 1599, and was for many years the most powerful magnate in Sussex, although from the turn of the century his principal residence was at Knole in Kent.
Returned for the fifth time for Sussex in 1604, Sackville was appointed to 22 committees, 16 of them in the first session, but made no recorded speeches. His father was elevated to the earldom of Dorset shortly before the session started, and consequently Sackville was usually referred to in the parliamentary records by the courtesy title, Lord Buckhurst. On 23 Mar. he was appointed to the committees established to consider the grievances raised by Sir Robert Wroth I and Sir Edward Montagu. Four days later he was also among those ordered to consider the problems arising out of the invocation of privilege on behalf of Sir Thomas Shirley I.
Having been appointed to the High Commission three years earlier, Sackville was an obvious choice for the committee on religion named on 16 April.
On 14 Apr. Sackville was appointed to attend the conference with the Lords on the Union with Scotland, and the same day was among those instructed to carry messages to the Lords about the same subject. He delivered further messages about the Union on 16th and 19 April. On 4 May he was appointed to confer with the Lords about drafting the bill for the Union commission and he was one of the commissioners nominated by the Commons on 12 May.
Sackville was the first named to consider a bill for the preservation of fish fry on 14 May and eight days later he was appointed to attend the conference with the Lords on wardship.
During the second session Sackville was named to attend conferences with the Lords on the recusancy laws (6 Feb. 1606) and ecclesiastical grievances (11 April).
Illness may have made Sackville less active in the third session. He attended the Union conference of 25 Nov. 1606, and was the first named to consider a bill intended to extend restrictions on the use of timber in the iron industry in East Sussex and on the border between Sussex and Kent (11 Mar. 1607). He was not named to the committee for the bill to enable his elder son Richard, a minor, to join him in surrendering their reversion to the office of chief butler, which was committed on 28 Mar. 1607 and reported three days later by Sir Henry Hobart.
In his will Sackville described his first wife as ‘a lady whilst she lived of as great virtue and worthiness ... as is possible for any man to wish or desire to be matched withal’.
Sackville attended the Twelfth Night festivities in 1608, reportedly losing £500 at play.
Sackville enjoyed his peerage for less than a year, and had no opportunity to take his seat in the House of Lords. After a ‘long sickness’ he drew up his will on 10 Feb. 1609 in the presence of his ‘faithful and dear friend’ Sir George Rivers, and of Richard Amherst* and William Twyneho*. The three witnesses were all remembered, and legacies were also left to Bowyer and ‘my honest servant Henry Bellingham*’. His wife was given only a life interest in her jewels and plate, with remainder to his stepson Sir Henry Compton*. His daughter was to receive a portion of £4,500 in all. Among lesser bequests to the poor, he entrusted to Rivers and Lord William Howard, his executors, the building and endowment of Sackville College at East Grinstead. Three days before his death his eldest son married celebrated Lady Anne Clifford, the niece of Francis Clifford*, apparently to frustrate the suits of the duke of Lennox and others for his wardship. Dorset died of the ‘distemper’ at his London house on 27 Feb., and was buried at Withyham with his ancestors and near his ‘first dearly beloved wife’. He requested that his funeral should not be that of a nobleman, as they were ‘only good for the heralds and drapers’. He had more regard for sculptors and stonemasons, ordering the expenditure of between £200 and £300 on a suitable memorial. His younger son, Sir Edward, sat for Sussex in 1621 before succeeding to the title on the death of his brother three years later.
