Further to
iain's comments about the New Model Army becoming a school for
radical politics, a few slightly dodgy historical notes from what I've read...
It could be said that the other feature that distinguished the New Model from most previous armies was its ideological, or perhaps spiritual would be better, commitment. They were God's saints in arms, who prayed and preached together, ushering in his millennium and doing battle with Antichrist.
The Army gave religious and political radicals a forum, and the turmoil of war removed many social checks to free expression.
The Grandees, that is the generals such as Ireton, Fairfax and Cromwell took a risk in calling the common people to arms to overturn the king, when as the Digger Gerrard Winstanley was to point out, the enemy they perceived was 'kingly power' per se, not just Charles as an individual.
The regiments appointed agitators, soldiers' representatives who presented demands not just on army matters but on political and religious questions too. There are records of the great debates held at Putney in 1647, where soldier's representatives discussed the Agreement of the People, a draft constitution put forward by the Levellers to ensure that the common people had not defeated a king just for a protector to take his place.
At Putney great Leveller figures opposed the Grandees' vision of mercantilism and property rights with a more democratic view of an enhanced franchise. Colonel Rainborough's words have become famous "The poorest he that is in England hath a life to live as the greatest he, and therefore...every man that is to live under a government ought first by his own consent put himself under that government.'
There was a fear of social revolution, and Cromwell began to attempt to re-impose army discipline and to 'break into pieces' these men,'If you do not break them they will break you'. This lead to the eventual crushing of the revolt at Burford in 1649, where Levellers lead a mutiny of soldiers refusing to serve in Ireland.
This write-up enhanced by valuable input from the Typo Death Squad. Thanks are due.