Critics agree that the form of sonnets was invented in Italy and initiated merely by the Italian sonnet Petrarch. Petrarch wrote his sonnets in English. As in novels at the beginning of the 18th century that were immature, unsophisticated and not well developed until the end of the 18th century, so were sonnets. Petrarch's sonnets in the 14th century can be considered as the first step in the evolution of sonnets. His language was somehow loose, his meanings vague and his themes simple. He dealt with simple issues concerning love, friendship, loyalty and some moral issues. He criticized his society and its demerits. He did not deal with critical, sensitive or controversial themes, this is why he chose a simple patterned rhyme scheme that was suitable for him to introduce his poetry. The sonnet is a form of a poem, but it is more restricted and sophisticated. It should be 14 lines, written in iambic meters and have rhymed line endings that rhyme in alternate with proceeding lines to suit his themes that did not emerge problems, and hence needed no solutions. Petrarch used the octave (8 lines) and sestet (6 lines) form. The octave rhymed abba abba and the sestet rhymed cde cde. He intentionally avoided the couplet form that suggested an end or a conclusion form because he did not ask a question in his sonnet that needed an answer nor did he suggest a problem in correspondence of a solution. He only criticized some demerits in his society or wrote about his feelings and emotions. The second stage of the evolution of sonnets was dedicated to the English Sonneteer Wyatt that brought the sonnet form into English and stated writing in it. Thus, the old form could not suit his ideas, so he modified it still using an octave and a sestet but the sestet reads then cdd cee. He, too, avoided reaching the couplet form because his themes too lacked sublimity and cruciality. He dealt with emotional topics avoiding controversial or universal ones, but he is remembered for being the first to modify a sonnet form and thus contributing to the progression of sonnets.
Now we can say that the highest point of evolution of sonnets was reached by Sir William Shakespeare. He introduced a totally different tract for dealing with and comprehending the sonnets. Now the themes have become in their utmost seriousness. New issues emerge, new analogies have to be dealt with. To him, the old themes were superficial, this is why he introduced new ones. The old rhyme schemes can no more comply to his themes. He was in need of a more developed pattern that is ductile. His themes, unlike the formers, should have then a conclusion at the end because he always reached at the end a situation totally different from that at the beginning of the sonnet, something happens to him and then his situation changes and becomes happy. The melancholy is introduced in the first stanza; the thing that changes his situation is introduced in the second and third stanza, and then his final situation is introduced in the last 13th and 14th lines, that are the concluding lines. This is why he was in need of modifying the former pattern to apply to him. Therefore, what is better for a conclusion than a couplet. Furthermore, the above pattern should totally be modified to be abab cdcd efef gg. This form was the best applicable to Shakespeare and the resulting sonnets still gather our attention till now. No doubt that this man did much to English literature and more precise to English sonnets.
He was the most famous sonneteer of his time (Elizabethan Age) and the later ages. His sonnet had universal themes that could not be attributed to one specific time or place. He wrote many famous plays, but still he was remembered for his sonnets. He was intelligent and knew that his themes could not be introduced in Petrarch's pattern or Wyatt's. Shakespeare wrote each line in iambic pentameter and the last words rhymed with an alternating line-ending word, for instance, the first line rhymed with the third-the second with the fourth-the fifth with the seventh-the sixth with the eighth etc. The last 2 lines (line 13 and 14) were rhymed like each other because they are the concluding lines. Unlike Petrarch and Wyatt who avoided completely reaching a conclusion and therefore a couplet form. Shakespeare was urged to reach a conclusion because the themes that he dealt with always with no failure must at the end show a change of state.
He modified the octave and sestet form initially used by Petrarch and Wyatt to 3 stanzas each being a quatrain (of 4 lines) and then a couplet.
Shakespeare's concern was immortality, poetry and friendship. He wrote 154 sonnets that are divided into 3 categories: immortality of poetry, his love for his friend, and his love for a woman. These topics are familiar direct, easy, simple and vivid.
The third sonneteer that contributed to the progression of English sonnets was Sidney. He was skillful and introduced new techniques. His writings were elegant, strictly to the point. He avoided figurative language and was perfect in writing a smooth, vivid poetry that lacked detailing. He criticized those poets that imitate other poets and advised them to write in their own ways or else they would be stealing other's techniques. The form of Wyatt did not suit his, so he modified the sestet to be ccd eed keeping the octave as it is. His poetry took 2 tracts: His beloved Stella whom he wrote to and to poetry.
