In vain did Fairfax solicit his release: Cromwell refused it, and Villiers remained in durance until the abdication of Richard Cromwell, when he was set at liberty, but not without the following conditions, dated February 21st, 1658-9:--
'The humble petition of George Duke of Buckingham was this day read. Resolved that George Duke of Buckingham, now prisoner at Windsor Castle, upon his engagement upon his honour at the bar of this House, and upon the engagement of Lord Fairfax in £20,000 that the said duke shall peaceably demain himself for the future, and shall not join with, or abet, or have any correspondence with, any of the enemies of the Lord Protector, and of this Commonwealth, in any of the parts beyond the sea, or within this Commonwealth, shall be discharged of his imprisonment and restraint; and that the Governor of Windsor Castle be required to bring the Duke of Buckingham to the bar of this House on Wednesday next, to engage his honour accordingly. Ordered, that the security of £20,000 to be given by the Lord Fairfax, on the behalf of the Duke of Buckingham, be taken in the name of His Highness the Lord Protector.'
During his incarceration at Windsor, Buckingham had a companion, of whom many a better man might have been envious: this was Abraham Cowley, an old college friend of the duke's. Cowley was the son of a grocer, and owed his entrance into academic life to having been a King's Scholar at Westminster. One day he happened to take up from his mother's parlour window a copy of Spenser's 'Faerie Queene.' He eagerly perused the delightful volume, though he was then only twelve years old: and this impulse being given to his mind, became at fifteen a reciter of verses. His 'Poetical Blossoms,' published whilst he was still at school, gave, however, no foretaste of his future eminence. He proceeded to Trinity College, Cambridge, where his friendship with Villiers was formed; and where, perhaps, from that circumstance, Cowley's predilections for the cause of the Stuarts was ripened into loyalty.
No two characters could be more dissimilar than those of Abraham Cowley and George Villiers. Cowley was quiet, modest, sober, of a thoughtful, philosophical turn, and of an affectionate nature; neither boasting of his own merits nor depreciating others. He was the friend of Lucius Cary, Lord Falkland; and yet he loved, though he must have condemned, George Villiers. It is not unlikely that, whilst Cowley imparted his love of poetry to Villiers, Villiers may have inspired the pensive and blameless poet with a love of that display of wit then in vogue, and heightened that sense of humour which speaks forth in some of Cowley's productions. Few authors suggest so many new thoughts, really his own, as Cowley. 'His works,' it has been said, 'are a flower-garden run to weeds, but the flowers are numerous and brilliant, and a search after them will repay the pains of a collector who is not too indolent or fastidious.'