Short answers, pulled from the story.
Oliver Cromwell was born in Huntingdon on the 25th of April 1599. He was baptised at St John's Church on the 29th of April 1599 and attended Huntingdon Grammar School before studying at Sidney Sussex College, Cambridge.
Cromwell came to believe, based on his reading of biblical texts and his interpretation of military victories as divine signs, that God had passed judgment against both the King and Parliament as lawful authorities. He was the third of 59 signatories to sign Charles I's death warrant. He also personally signed the order for the actual execution when officers refused to do so.
At the Siege of Drogheda in September 1649, Cromwell's troops killed nearly 3,500 people after the town's capture, comprising approximately 2,700 Royalist soldiers and all men found carrying arms, including some civilians, prisoners, and Catholic priests. Cromwell justified the killings on the grounds that the garrison had refused to surrender even after the walls were breached.
Cromwell was sworn as Lord Protector on the 16th of December 1653 under a constitution called the Instrument of Government. He was paid £100,000 a year, led the executive with a Council of State, dissolved two Protectorate Parliaments, divided England into military districts ruled by major generals, ended the First Anglo-Dutch War, and captured Jamaica in 1655. He refused the offer of the Crown in 1657 but was re-installed as Lord Protector at Westminster Hall on the 26th of June 1657.
Cromwell died at age 59 at Whitehall on the 3rd of September 1658, most likely from sepsis following a urinary infection complicated by malaria. He was buried at Westminster Abbey. On the 30th of January 1661 his body was exhumed, hanged in chains at Tyburn, and thrown into a pit. His head was displayed on the roof of Westminster Hall until at least 1684, and was eventually buried at Sidney Sussex College, Cambridge, in 1960.
Cromwell's 1649-1650 campaign in Ireland included the massacres at Drogheda and Wexford, where several thousand soldiers and civilians were killed. Following his departure, the Act for the Settlement of Ireland 1652 confiscated all Catholic-owned land and confined remaining Catholic landowners to Connacht under threat of execution. The 17th-century economist William Petty estimated 600,000 excess deaths in Ireland across the Wars of the Three Kingdoms period. Winston Churchill wrote that Cromwell's Irish record was 'a lasting bane' and noted that 'the curse of Cromwell' remained a concentrated expression of hatred centuries later.