In his short story, "The Portrait of Mr. W.H.," Oscar Wilde explores a theory, which he may or may not actually have believed, about the mysterious figure to whom Shakespeare's sonnets are dedicated. In popular Shakespearean scholarship, only the pastime of finding alternative authors for the plays, from the Earl of Oxford to Christopher Marlowe, has occasioned more theories than the search for a story behind Shakespeare's sonnets.
The following statements are relatively uncontroversial. The majority of Shakespeare's sonnets (1-126) are addressed to a young man, apparently of noble birth, whom Shakespeare loves. The addressee is younger than the poet and is often called "the fair youth." The later sonnets refer, in rather less admiring terms, to a woman Shakespeare also loves, known as "the dark lady." Many poems refer to Shakespeare's hopes of achieving immortality through his poetic gifts, and these sometimes refer to a "rival poet." There have been various theories identifying the fair youth, the dark lady, and the rival poet. Perhaps the most popular have said that the fair youth is either the Earl of Pembroke or the Earl of Southampton, while the dark lady is Mary Fitton, and the rival poet is Christopher Marlowe (who has also been suggested, very implausibly, as a possible author of Shakespeare's plays).
While certain sonnets do seem to be making references to details of Shakespeare's life, such as the closing of theaters due to the plague, what is very clear is that they record what was most important to him, primarily his intense personal relationships and his hopes of achieving greatness through his poetry. In this sense, the sonnets certainly record Shakespeare's personal experience, but any more precise narrative is always likely to remain controversial.