His artistic contacts were more peaceful and more significant for his lasting fame. During his absence from court, he wrote Astrophel and Stella and the first draft of The Arcadia and The Defence of Poesy. Somewhat earlier, he had met Edmund Spenser, who dedicated The Shepheardes Calender to him. Other literary contacts included membership, along with his friends and fellow poets Fulke Greville, Edward Dyer, Edmund Spenser and Gabriel Harvey, of the (possibly fictitious) 'Areopagus', a humanist endeavour to classicise English verse.
Sidney had returned to court by the middle of 1581 and in 1584 was MP for Kent. That same year Penelope Devereux was married, apparently against her will, to Lord Rich. Sidney was knighted in 1583. An early arrangement to marry Anne Cecil, daughter of Sir William Cecil and eventual wife of de Vere, had fallen through in 1571. In 1583, he married Frances, teenage daughter of Sir Francis Walsingham. In the same year, he made a visit to Oxford University with Giordano Bruno, who subsequently dedicated two books to Sidney.