If Charles had been the last of his line, there would have been an intelligible reason for putting him to death.  But the blow which terminated his life at once transferred the allegiance of every Royalist to an heir, and an heir who was at liberty.  To kill the individual was, under such circumstances, not to destroy, but to release the King.

We detest the character of Charles; but a man ought not to be removed by a law ex post facto, even constitutionally procured, merely because he is detestable.  He must also be very dangerous.  We can scarcely conceive that any danger which a state can apprehend from any individual could justify the violent, measures which were necessary to procure a sentence against Charles.  But in fact the danger amounted to nothing.  There was indeed, danger from the attachment of a large party to his office.  But this danger his execution only increased.  His personal influence was little indeed.  He had lost the confidence of every party.  Churchmen, Catholics, Presbyterians, Independents, his enemies, his friends, his tools, English, Scotch, Irish, all divisions and subdivisions of his people had been deceived by him.  His most attached councillors turned away with shame and anguish from his false and hollow policy, plot intertwined with plot, mine sprung beneath mine, agents disowned, promises evaded, one pledge given in private, another in public.  “Oh, Mr. Secretary,” says Clarendon, in a letter to Nicholas, “those stratagems have given me more sad hours than all the misfortunes in war which have befallen the King, and look like the effects of God’s anger towards us.”

The abilities of Charles were not formidable.  His taste in the fine arts was indeed exquisite; and few modern sovereigns have written or spoken better.  But he was not fit for active life.  In negotiation he was always trying to dupe others, and duping only himself.  As a soldier, he was feeble, dilatory, and miserably wanting, not in personal courage, but in the presence of mind which his station required.  His delay at Gloucester saved the parliamentary party from destruction.  At Naseby, in the very crisis of his fortune, his want of self-possession spread a fatal panic through his army.  The story which Clarendon tells of that affair reminds us of the excuses by which Bessus and Bobadil explain their cudgellings.  A Scotch nobleman, it seems, begged the King not to run upon his death, took hold of his bridle, and turned his horse round.  No man who had much value for his life would have tried to perform the same friendly office on that day for Oliver Cromwell.