What inspired shakespeare to write his plays?

From great classical authors like Ovid and Seneca, to English historians like Holinshed, Shakespeare's greatest influences were the works of other great writers. With the exception of A Midsummer Night's Dream, Love's Labour's Lost and The Tempest, which are wholly original stories, Shakespeare borrowed his plots, down to fine detail. You can read about what Shakespeare read as he crafted each play in my sources section. Here is a brief biography of two of Shakespeare's favourite authors: 

Geoffery Chaucer (1340-1400)
Even though Chaucer wrote his poetry in Middle English, he is still regarded as one of England's finest poets. Chaucer was born into a wealthy family and his father, John, spent time at the court of King Edward III as a deputy to the King's butler. His father's ties to the royal family helped Geoffery acquire a position at court, and he became a permanent member of the King's household. In 1368, Chaucer was listed among the King's esquires, and, in 1369, shortly after the death of Queen Philippa, he wrote his first major poem, Book of the Duchess. The work for which Chaucer is most noted is the Canterbury Tales, in which a group of pilgrims gather at the Tabard Inn in Southwark, across the Thames from London, and agree to a storytelling contest as they travel to the shrine of Thomas à Becket in Canterbury, Kent. Chaucer died in 1400 and he was the first poet ever to be buried in the "poet's corner" in Westminster Abby. Shakespeare undoubtedly admired Chaucer works immensely, for he uses several of Chaucer's poems as sources of his plays. Troilus and Criseyde was the primary source of Troilus and Cressida, and the Parliment of Fowles was a source of Mercutio's "Queen Mab" speech in Romeo and Juliet. It is apparent that The Knight's Tale sparked Shakespeare to craft the The Two Noble Kinsmen, and there are several other minor examples one could cite.

Plutarch (46-120 AD)
Plutarch was the son of Aristobulus, an important biographer and philosopher. In 66-67, Plutarch studied philosophy and mathematics at Athens under the philosopher Ammonius. After studying with Ammonius, Plutarch became a teacher of philosophy in Rome and earned the admiration of the emperors Trajan and Hadrian. But Plutarch was not content to stay in Rome and, after Trajan's death, Plutarch traveled widely, to central Greece, Sparta, Corinth, Sardis, and Alexandria. Although he was away much of the time, his main residence was Chaeronea, a small Greek town on Mt. Petrachus, guarding the entry into Boeotia from the North. Plutarch is best known for the work Parallel Lives, which consists of the biographies of notable soldiers and statesmen. Plutarch's Lives was translated by Sir Thomas North in 1579 and the work grew very popular in Renaissance England. Shakespeare himself used North's translation of Parallel Lives as the primary source for Antony and Cleopatra, Julius Caesar, Coriolanus, Timon of Athens, and a minor source in several other plays. It is a testament to the quality of North's translation that Shakespeare copied whole passages from the work, making only the smallest of changes. Plutarch's influence upon others writers through history is just as profound - Otway used Lives as a source for Caius Marius, and Addison used the same as a souce for Cato. Among Plutarch's greatest admirers have been Michel de Montaigne, Mary Shelley, Napoleon, Milton, and Ralph Waldo Emerson, who once wrote: "Go with mean people and you think life is mean. Then read Plutarch, and the world is a proud place, peopled with men of positive quality, with heroes and demigods standing around us, who will not let us sleep"

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