The grandson of the Duke of Northumberland and heir presumptive to the earls of Leicester and Warwick, Sir Philip Sidney was not himself a nobleman. Today he is closely associated in the popular imagination with the court of Elizabeth I, though he spent relatively little time at the English court, and until his appointment as governor of Flushing in 1585 received little preferment from Elizabeth. Viewed in his own age as the best hope for the establishment of a Protestant League in Europe, he was nevertheless a godson of Philip II of Spain, spent nearly a year in Italy, and sought out the company of such eminent Catholics as the Jesuit martyr Edmund Campion. Widely regarded, in the words of his late editor William A. Ringler, Jr., as "the model of perfect courtesy," Sidney was in fact hot-tempered and could be surprisingly impetuous. Considered the epitome of the English...