Ellis was second son of
Sir Thomas Ellis of
Grantham, Lincolnshire. He was educated at
Christ's College, Cambridge, graduating B.A. in 1627. Having entered
Gray's Inn on 6 November 1627 he was called to the bar on 9 February 1634. He represented
Boston, Lincolnshire, in the
Short Parliament of 1640, and also in the
Long Parliament. After
Pride's Purge Ellis was readmitted to the House of Commons on 4 June 1649. On 24 May 1654, he was appointed
solicitor-general. Shortly afterwards he was elected an ancient of his inn. As solicitor-general he took part in the prosecution of those involved in the
Gerard's conspiracy:
John Gerard,
Peter Vowell, and
Summerset Fox on the charge of corresponding with
Charles Stuart and conspiring to assassinate the
Lord Protector Oliver Cromwell. The trial took place in June 1654. Gerard and Vowell pleaded innocent. They were convicted and sentenced to death. Gerard was beheaded and Vowell was hanged (Fox pleaded guilty and was sentenced to transportation). The same year, Ellis was again returned to Parliament for Boston, and in 1656 for
Grantham. He was a member of the committee appointed to frame statutes for
Durham College in March 1656. In June 1658, he was engaged in the prosecution of
John Hewett and
John Mordaunt, charged with levying war against the Protector. Hewett was found guilty and Mordaunt acquitted. He was created a baronet by the Lord Protector Oliver Cromwell on or soon after 31 May 1658. The baronetcy passed into oblivion at the
Restoration in May 1660 and unlike some others was not renewed. Ellis continued in the office of solicitor-general under the second Lord Protector
Richard Cromwell. At the election in January 1658-59 for the
Third Protectorate Parliament he retained his seat for Grantham. In the debate on the competency of the Scottish members he spoke at length in support of their claims (18 March 1659). Re-elected for Grantham in 1660, Ellis was excluded from the house on the score of his opinions. In autumn 1664 he was appointed reader at Gray's Inn, of which he had been elected a bencher in 1659; on 26 August 1669 he took the degree of
serjeant-at-law, and, on 10 April 1671, he was advanced to the rank of king's Serjeant and knighted. He was raised to the bench in 1673, taking his seat in the
Court of Common Pleas on the first day of Hilary term. The only case of public interest which came before him was that of Barnardiston v. Swaine, an election case. Ellis was removed in 1676, without reason assigned, but reinstated on 5 May 1679, having been returned to parliament for Boston in the preceding February. He sat as one of the judges at the last of the major
Popish Plot trials, when
Lionel Anderson and six other
Catholic priests were tried on the capital charge of acting as priests in England, contrary to the statute of 1585. In contrast to previous Plot trials, the proceedings were conducted in a courteous and civilized fashion, and though the priests were found guilty and sentenced to death, they were all reprieved. He died on 3 December 1680 at his chambers in
Serjeants' Inn. ==Notes==