Prior to the restoration of the throne there was eleven years of Interregnum in England. This was a period in England's history where the country was run without a Monarch; it was dominated by a man called Oliver Cromwell. During the Interregnum there were parliaments created to run the country, they were introduced by the army which had began to play politics before the execution of Charles I. All of these experiments failed mainly due to one key reason: Cromwell was a perfectionist. He demanded nothing short of excellence in all aspects of government. He wanted to create a heaven on Earth in England.
Another issue that loomed in the background was the lack of a stable settlement which suited the Governing Class. Particularly relevant to the decision to restore Charles II to the throne was the fact that England was unstable after Cromwell's death (1658). His son (Richard Cromwell) was to take over but lacked respect within the army and subsequently failed to control it.
"The great rebellion had collapsed from within." - Woolrych.
At this stage England entered a stage of political bankruptcy. The Rump was restored for the second and third times, it was hardly successful and it seemed that nothing would work. The political nation of England had ran out of ideas. There was, however, a sound model sitting in the back of most people's minds - get a King back!
Charles was careful here, he didn't want to make any rash decisions or sudden movements that might turn the political tide away from his favour, remember there was a Royalist uprising in late 1659 that wasn't supported and easily put down by England's standing army.
This is where a man called Monck stepped in, he was a Scottish General in charge of a large Scottish army. He decided that it was high time the English army stopped playing politics and the monarchy in England was restored. He moved South from Scotland, defeating a number of English armies on his way.
Monck arrived in London and ordered the current government, the third Rump, to dissolve. But before doing so, he called back all of the remaining members to sit (a lot had died) so they could pay the current standing army. Parliament was dissolved and the army was ordered to disband. Monck was in control.
Monck was playing the role of a catalyst, he realised that the governing class was beginning to get a little worried about the Quakers, Diggers and Levellers. They were worried about a governed class takeover.
Hyde and Monck coaxed the governing class into readily accepting Charles II's proposal (presented to the House of Lords, House of Commons, the Army, the Navy and the City of London) of his re-instatement to the throne by waiting for public pressure to build and then manipulating it in their own favour.
Contributing factors for Charles II's restoration include (but are not limited to) the failure of the Interregnum experiments, the governing classes almost everyone not actually wanting Charles I executed and the monarchy abolished, fear of a governed class uprising and of course the most important of all: the current lack of stability of government.
This series of essays (Decision to..) were written in preparation of exams in a weeks time. Wish me luck. Please feel free to /msg me with suggestions of what I could add, remove, edit, etc. Anything that is inaccurate I'd appreciate it if you gave me your opinion :) Special thanks to iamkaym for your comments.\