The sonnet, a 14-line poem, originated in medieval Italy. Its traditional subject is love, namely romantic love. In fact, in 17th-century England, "sonnet" was sometimes used to refer more to themes than to form. Only one of the poems in John Donne's "Songs and Sonnets" is technically a sonnet, while many of them pertain to matters of love and lust. Although traditional sonnets have the subject of love in common, their loves are not all the same. The affections expressed in a sonnet differ depending on their object.
The other term for Italian sonnet is Petrarchan sonnet, which reflects just how crucial Petrarch is to the sonnet's development and popularity. Petrarch perfected the quintessential pose of the suffering lover who is devoted to his unattainable beloved. However other poets, including Dante and Guinicelli, also contributed importantly to the form. The medieval concept of courtly love informed these sonnets' idealization of the women, whose features the verses inventoried and praised. The Petrarchan twist on courtly love is unfulfillment. The quintessential sonnet speaker has the all the obsequiousness of a knight, but none of his success. In 16th-century England, Sir Philip Sidney carried on this tradition with the sequence "Astrophil and Stella."
The sonnet underwent another change when it arrived in England. It remained a way to express feelings of romantic love, and it continued to be voiced by a lovesick man, but it no longer portrayed an angelic blonde, "Donna." The writer chiefly responsible for introducing the Italian form to English, Thomas Wyatt, described love that had a deleterious, not uplifting, effect on its host. The sonnets by Shakespeare that address a "dark lady" resemble Wyatt's poetry in this respect.
Classic sonnets by women also concern themselves with romantic love. The most famous examples come from the Victorian period, specifically from the work of the poets Christina Rossetti and Elizabeth Barrett Browning. Both authors acknowledge the sonnet's continental origins, as is evident the in the titles of their respective sonnet sequences, "Monna Innominata" and "Sonnets from the Portuguese." In these sonnets, the beloved individual is not idealized and unattainable, but his literal absence makes him inaccessible and thus allows the poetess to write about love introspectively. "Monna Innominata" is especially interesting because Rossetti opens it by positioning herself opposite the Petrarchan tradition explicitly.
If English poets of the 1590s retained the fleshly currents of Italian sonnets but discarded the ethereal aspects, John Donne did the reverse. His "Holy Sonnets" apply the form to theological themes. Yet even these show that the sonnet form is more than a rhyme scheme; Donne addresses God the way other sonneteers addressed their beloveds, and his metaphors sometimes have erotic qualities. The sonnet's ability to detail the intricacies of moods and to dramatize inner conflict make it compelling, and Donne carries this intimacy and immediacy into his religious reflections.