Not sure that Cromwell was particularly invassociated with planting Scots in Ireland. Original plantation in the early 1600s was in the reign of James VI of Scotland and I of England. Planter community came under attack in the 1640s by Irish Confederates and Scottish Parliament sent an army to Ireland to protect them whilst at the same time occupying Northern England in an all
iance with the English Parliamentarians. The Scots and Cromwell fell out after the execution of the King hence when Cromwell looked to renew the planting he favoured the English as planters rather than Scots. With the Restoration of the Stuart monarchy the Presbyterians were oppressed in Scotland so no doubt some may have moved away. However as far as I understand it the first mass movement since the early days of the Plantation happened in the 1690s. The famine and so called "I'll years" resulted in tens of thousands leaving Scotland.