The 1647 Putney Debates saw the development of many of the key democratic ideas we take for granted today. As Thomas Raisborough put it. 

the poorest he that is in England has a life to live, as the greatest he: and therefore truly, Sir, I think it is clear, that every man that has a life to live under a government ought first by his own consent to put himself under that government; and I do think that the poorest man in England is not bound in a strict sense to the government that he has not had a voice to put himself under

All of this was of course against the backdrop of the English Civil War which in many ways makes if even more remarkable.