Oliver Cromwell
Cromwell didn't waste any time taking over after he'd succeeded in having Charles I's beheaded.  He saw the perfect opportunity and he took it. He had no wish to let England discover that his victory had been with a meagre army of barely 20,000 opportunistic, military and religious fanatics. To keep them in their place, he wanted the people to believe it had been with a ruthless army that would not hesitate to deal with any other rebels and he was prepared to use that army anyway he saw fit. Before England knew it, he showed what he was capable of and declared that the House of Lords was useless before he abolished it.
Perhaps Cromwell had forgotten why Charles had been executed but Parliament hadn't. Outrage turned to shock when Cromwell then declared he would be sending his army to fight against 'the idolatrous and blood-stained Papists in Ireland' .
What they'd expected was for him to do something about the Dutch, not the Irish. English resentment was growing as the Dutch were steadily growing richer because the Dutch system was classed as 'free trade' while the English good still had heavy duties and taxes laid on them. As a result, Dutch products were less expensive in the world market while England was struggling to cope. When Cromwell, true to his word, began his brutal, cold-blooded attack on Drogheda on September 3rd 1649, they were looking at each other in open-eyed fear. 
But the worst was yet to come.