King Charles I came to the thrones of Scotland , England and Ireland in 1625, he very much liked being king and especially liked being head of the Church of England. He decided to impose this on Scotland, together with the introduction of bishops and a new book of prayer. Many of the people of Scotland were not impressed and the struggle began. The Scots reintroduced a National Covenant from the sixteenth century and the adherents were called Covenanters. The Covenanters gave Charles as good as they got and Charles had to recall the English Parliament when he ran out of money. This started the English? Civil War and the Covenanters joined with Cromwell to defeat Charles after the signing of the Solemn League and Covenant which ensured a Presbyterian religion in both countries.
When Cromwell's roundheads executed King Charles I in 1649 they rather overlooked the point that he was not only King of England but also King of Scotland. The people and nobles of Scotland suddenly finding themselves kingless, proclaimed his son as King Charles II of Scotland but took the precaution of making him sign the Solemn League and Covenant to try to prevent him following his father in attempting to impose the beliefs of the English church on Scotland. The negotiations to the signing (not to mention the fighting) took until 1651 and he was duly crowned. Inevitably he decided to invade England and was trounced at Worcester, this left Cromwell in outright control of Scotland, England and Wales. Charles II fled to the continent where he remained until 1660. Returning as king he repudiated his signing of the Covenant and continued his father's campaign. After his death the campaign of terror against the Scottish Covenanters was continued by his brother James with increased venom until his ejection in 1688 and replacement by William and Mary.
In the intervening years the UK was ruled by Cromwell and his associates as a republic called 'The Commonwealth'. Cromwell's army invaded Scotland, suppressed any opposition and proceeded to occupy the country. He built large forts called 'Citadels', smaller forts and garrisoned many castles across the country. This website tells the story of the citadels, forts and castles, it also tells of the castles attacked by Cromwell's forces from 1650 onwards.
This website originally existed as three separate websites - Cromwell's Citadels, Cromwell's Forts and Cromwell's Ruins. They were terminated, with many other websites, when my then ISP decided to scrap all websites it hosted in favour of a new system more suitable for personal websites.