He relieved the town with great dash, but was so eager to press on that he would not even wait to speak to the governor, Lord Newcastle, who was very offended at what he considered to be a want of respect. Still more angry was he when he received a message from Rupert commanding him to follow the cavalry without delay. He made no haste to carry out this order, and Rupert, who was in close touch with the enemy, waited for him in vain. The delay cost the Royalists dear, for the battle of Marston Moor which ensued was a complete triumph for the Roundheads. But even then Rupert did not lose heart, as did so many of his party.
"'What will you do?' asked General King of him. 'I will rally my men,' sayes ye Prince. Sayes General King, 'Nowe what will my Lord Newcastle do?' Sayes he, 'I will go to Holland, for all is lost.'"
The defeat of the Northern army was decisive, and Rupert felt the only help lay in Wales and the west of England. But defeat followed defeat. At Naseby the Parliamentary army was again victorious; Bristol surrendered, then Oxford. Nor was this all. Among the king's nearest advisers were many who disliked Prince Rupert, especially Lord Digby, and when the Prince surrendered Bristol, he saw his opportunity for revenge. Very cleverly he worked on Charles to such an extent that he made it appear as if Rupert had weakly capitulated without any justification, and the king, who all too easily forgot the past, signed an order revoking the military authority and position he had bestowed on his nephew. The Prince was sorely hurt and indignant at this want of confidence. "It is Digby that is the cause of all the distraction," he said quietly, and then proceeded to defend his honour and his action, which he did in a manner that commended itself to all fair-minded men.
Having written a full account of the siege, and proved that holding out longer would have only meant a useless sacrifice of valuable lives, he followed this up by going straight to the king at Newark, in spite of having been forbidden to do so by Digby. "I am come, sir," he said, "to render an account of Bristol." At first Charles would not listen, but Rupert insisted on a court-martial, which at last was granted, and which completely cleared him. The king accepted the verdict, but in a half-hearted way, which nettled the Prince, who was already chafing at the unjust accusations made against his honour. A few days later he vigorously fought the battle of another officer who had been dismissed—also the victim of Digby's jealousy.
"No officer," he declared indignantly, "should be deprived of his commission without being able to defend himself against a council of war."
In his anger he applied to Parliament for permission to return to Holland, but when the message came that this would only be given on condition that he did not fight again, he indignantly refused the terms. His loyalty was deeper than his anger when it came to the test.
Ere long, however, the hopeless, weary struggle reached its end. The king threw himself on the mercy of his Scottish army, who for £400,000 gave him up to Parliament, and he was made a prisoner. Rupert found his way to France, and later on he joined the Prince of Wales in getting together a small fleet which it was proposed to send to Ireland. He entered enthusiastically into this new career. "The royal cause," he said, "is now at sea." Far and wide on the ocean he was to be heard of with his ships, round Spain, Portugal, in the Mediterranean and the West Indies, near Azores and Cape Verde, seizing wherever he could find them the treasure-ships belonging to the English Parliament. His name was a terror by sea as it had been by land, and the adventurous life was quite according to his liking. With the Restoration he came back to England, and Charles settled on him an allowance of £4000 a year, besides giving him an important command in the fleet. But no real scope was allowed him for his powers, and Charles, with all his foreign intrigues, found Rupert too inconveniently straightforward and resolute.
So the end of his life was a disappointment, though when action of one sort was denied him, his eager brain turned to science, chemistry, and inventions. Most of his old friends had vanished; his mother had died many years before, protected and comforted to the last by Lord Craven, who had taken for a motto the words "For God and for Her;" and of his sisters, one was an abbess, the other married to the Elector of Hanover.
He lived alone and quietly at his house in Spring Gardens at the top of Whitehall, and when he died, comparatively young, he was "generally lamented for an honest, brave, true-hearted man, whose life had embraced innumerable toils, and a variety of noble actions by land and by sea."
"It is an infinite pity he is not employed according to his genius," a friend of his mother's had written to her long years before. "He is full of spirit and action, and may be compared to steel, which is the commanding metal if it be rightly tempered and disposed. Whatever he wills, he wills vehemently."