was made to construct a completely new code of laws on unheard-of principles, Cooper busied himself with passing into law the recommendations of the commission above mentioned for cheapening legal proceedings and facilitating conveyancing. The reform of the court of chancery was not, however, carried, nor was he successful in passing a bill for the repeal of the ‘engagement.’ In the debate on tithes, the question upon which the Protector determined to break up the Barebones parliament, he supported Cromwell in desiring that they should be continued. On 12 Dec. a vote, moved by one of Cooper's friends, was passed, by which the parliament put an end to its own existence and gave up its powers to Cromwell. According to Burnet, he was one of those who urged Cromwell to accept the crown, and his desire to secure fair representative government makes the statement probable. He had been immediately appointed on the new council of state of fifteen members, but he never received the salary of 1,000l. a year attached to the office. In the election to the new parliament, which turned on the contest of moderates against republicans, Cooper was chosen for Wiltshire, Poole, and Tewkesbury, and elected to sit for Wiltshire. This county had ten members, and ten candidates were proposed by the cavaliers, presbyterians, and Cromwellites combined, against ten republicans headed by Ludlow. Cooper and Byfield addressed the electors from Stonehenge, and all the moderates were elected with Cooper at their head. During the eight months previous to the meeting of parliament he took part in the repeal of the engagement, the settlement of the terms of union with Scotland, and the attempted reform of chancery, and acted as one of the commissioners for ejecting unworthy ministers.
The house met on 3 Sept. 1654, and was dissolved on 22 Jan. 1655. On 28 Dec. 1654 Cooper made his last appearance at the privy council. He had acted strongly with Cromwell while he appeared to be trying for genuine parliamentary government, and was probably compelled to break away from him when he saw that the Protector was now disposed to rule alone; but it is curious that as late as 27 Nov. he was, with Richard Cromwell, a teller in one of the divisions. His second wife died in 1654, leaving two sons, of whom one died in childhood, and the other, Anthony Ashley, succeeded him. Ludlow states that the reason of the breach with Cromwell was Cooper's unsuccessful suit to Mary Cromwell (Carlyle, Letters and Speeches of Cromwell, iii. 151), but this seems most improbable (Christie, p. 120 n.) On 30 Aug. 1655 he was married a third time, to Margaret, daughter of the second Lord Spencer of Wormleighton, and sister of the Earl of Sunderland, who had been killed at Newbury (Gent. Mag. 1850, ii. 367). By this wife, who survived him till 1693, Cooper had no children. She was a woman of an intensely devotional character, but they lived on terms of the warmest affection.
When the new parliament met, on 17 Sept. 1656, Cooper appeared in opposition to Cromwell, at the head of a coalition of presbyterians and republicans. He was again elected for Wiltshire, under the provisions of the Instrument of Government. Cromwell, however, taking advantage of the requirements of the Instrument that all members must possess the council's certificate, would not allow him to take his seat. With sixty-four members similarly excluded, he signed a protest to the speaker, which was delivered by Sir G. Booth, a presbyterian royalist. This proving useless, a remonstrance was drawn up in terms of the most uncompromising opposition to Cromwell, and Cooper's name appears among those of the 93 (or, according to Whitelocke, 116) members who signed it. By the petition and advice, passed on 25 May 1657, the Instrument was superseded, and two houses of parliament were again created. Cooper's name did not appear in the list of ‘peers.’ Cromwell, it is said, declared that no one was so difficult to manage as the little man with three names (Martyn, Life, i. 168). And yet there was evidently no great enmity between them; for it was now (January 1658) that the fine of 500l., imposed on Cooper by the Long parliament for delinquency, was discharged by Cromwell on the former's petition; and it is certain that Cooper and Henry Cromwell were on terms of intimacy. When the new parliament met, on 20 Jan. 1658, the former House of Commons being by the terms of the petition and advice still in existence, the members previously excluded, Cooper among them, took their seats. They immediately began a vigorous opposition; they denied the legality of the petition and advice, and they especially refused to admit the claims of Cromwell's House of Lords. In this opposition Cooper took a leading part, speaking frequently and well. He urged the commons first of all to debate the title which the other house should bear. ‘Admit lords,’ he said, ‘and you admit all.’ He strongly supported the motion for a grand committee, by which the utmost opportunity can be afforded for obstruction. It was defeated, Cooper being one of the tellers of the ‘ayes.’ Dissatisfied, however, with the smallness of the majority,
