Oliver Cromwell rose to power in the civil conflicts which led to the execution of King Charles I in 1649. He ruled as Lord Protector of the Commonwealth of England, Scotland and Ireland from 1653 until his death in 1658. He campaigned in Scotland during 1650-52, but never visited Ayr. After his return to England, part of the occupation force he left behind built a major citadel fortress at Ayr, and Cromwell Road runs parallel to a surviving stretch of its wall. (It had previously been Gas Work Road, the name being changed in 1902.)
While Cromwell has been admired as a defender of parliamentary democracy against absolute monarchy, he has also been viewed as having become virtually a military dictator whose Puritan rule was increasingly resented.
The most controversial part of his career is his 1649 campaign in Ireland. In an age when there was very little religious toleration anywhere in Europe, Cromwell enforced repressive measures against Roman Catholics in general and Irish Catholics in particular. An Irish Catholic rebellion which broke out in 1641 had resulted in the deaths of many Protestant English and Scottish settlers, though not as many as was claimed at the time. When Cromwell's troops stormed Drogheda, he gave orders that no mercy was to be shown to any who had borne arms in its defence, and he saw to it that these orders were carried out. There was also a considerable loss of civilian life, although it has been questioned if this was as great as has been traditionally claimed. When Wexford was stormed there was again a heavy death toll. It has been pointed out that, at this time, if a town's defenders refused an invitation to accept surrender terms, they could not expect to receive any mercy if the town was stormed, and it would then be given over to plunder. However - at least at Drogheda - Cromwell appears to have been more ruthless than had been usual in sieges in England. (Although when Dundee was stormed by Cromwell's commander in Scotland, General Monck, a similar massacre followed.) After Cromwell returned to England, other commanders completed the crushing of rebellion in Ireland and then pursued a policy of repression, mass deportation to the West Indies and confiscation of land resulting in widespread starvation.
It has been argued that this amounted to near-genocide, but there has been much debate about the extent to which Cromwell can be held personally responsible for it. In Ireland, however, many associate his name with all the oppression which took place during this period.