Question: What William Shakespeare play was written in 1599 and based on true events in Roman history?

Context paragraphs:
Julius Caesar (play): The Tragedy of Julius Caesar is a tragedy by William Shakespeare, believed to have been written in 1599.  It is one of several plays written by Shakespeare based on true events from Roman history, which also include "Coriolanus" and "Antony and Cleopatra".

Love's Labour's Lost (film): Love's Labour's Lost is a 2000 adaptation of the comic play of the same name by William Shakespeare, directed by and starring Kenneth Branagh.  It was the first feature film to be made of this lesser-known comedy.  Branagh's fourth film of a Shakespeare play (he did not direct the 1995 "Othello", although he did play Iago), "Love's Labour's Lost" was a box-office and critical disappointment.

Love's Labour's Won: Love's Labour's Won is a lost play attributed by contemporaries to William Shakespeare, written before 1598 and published by 1603, though no copies are known to have survived.  Scholars dispute whether it is a true lost work, possibly a sequel to "Love's Labour's Lost", or an alternative title to a known Shakespeare play.

Shakespeare's Globe: Shakespeare's Globe is the complex housing a reconstruction of the Globe Theatre, an Elizabethan playhouse associated with William Shakespeare, in the London Borough of Southwark, on the south bank of the River Thames.  The original theatre was built in 1599, destroyed by fire in 1613, rebuilt in 1614, and then demolished in 1644.  The modern Globe Theatre reconstruction is an academic approximation based on available evidence of the 1599 and 1614 buildings.  It is considered quite realistic, though contemporary safety requirements mean that it accommodates only 1400 spectators compared to the original theatre’s 3000.

Thomas J. King Jr.: Professor Thomas J. King Jr. (July 25, 1925 – 1994) was an educator, and an early user of word processing and sequence analysis to compare available early versions of William Shakespeare's plays for identification of variant texts and their analysis.  Dr. King's historical work also researched original prompt copies of Elizabethan Era and Jacobean Era plays contemporary to Shakespeare, along with their marginalia, in order to identify stage directions and infer physical staging of Shakespeare's plays at the Globe and other London venues, as well as at provincial halls and inns where Elizabethan troupes performed on tour.  In his extensive studies, Prof. King created databases of every Shakespeare play and other extant Elizabethan contemporary playhouse documents, by scene and character, to determine number of lines, and therefore the roles that could be doubled with sufficient time between for costume change, thus enabling him to determine the size of a working Elizabethan theater company.

Le piccole storie: Le piccole storie, subtitled "Ai margini delle guerre", is a one-act chamber opera for young people by Lorenzo Ferrero set to an Italian-language libretto by Giuseppe Di Leva.  Some episodes are loosely based on Guy de Maupassant's 1884 short story "Le Lit 29" and on William Shakespeare's play "Julius Caesar".  The stories do not touch directly upon the subject of war but depict moments in the lives of involuntary victims who subsist, as the subtitle suggests, on the margins of wars.

Into the Gauntlet: Into the Gauntlet is the tenth book in "The 39 Clues" novel series.  It was written by Margaret Peterson Haddix and released on August 31, 2010.  In the beginning of the book, Amy and Dan are now at the end of their clue hunt, and every misfortune they've had.  Their lead is a poem found in their hotel room.  However, it is then stolen by Isabel Kabra.  It is revealed that William Shakespeare was a powerful Madrigal and the most important clue is on the line against their competitors.  Dan and Amy are supposed to go to the Globe theater to watch a Shakespeare play, "Romeo and Julliet".  While watching the show they see what looks to be ninjas.  The ninjas find a clue at the top of the theater but drop it into the hands of Dan and Amy.  As it turns out the whole Cahill family is at the play looking for the clue.  Backstage of the play the fight over the paper found at the theater.  Mr. McIntyre and Fiske Cahill reveal there is another family out there that makes Isabel Kabra look like Mother Teresa.  The globe on the 39 Clues symbol is, unlike in the first nine books, shattered into pieces.

The Merchant of Venice: The Merchant of Venice is a 16th-century play by William Shakespeare in which a merchant in Venice must default on a large loan provided by an abused Jewish moneylender.  It is believed to have been written between 1596 and 1599.  Though classified as a comedy in the First Folio and sharing certain aspects with Shakespeare's other romantic comedies, the play is perhaps most remembered for its dramatic scenes, and it is best known for Shylock and the famous "Hath not a Jew eyes?"  speech.  Also notable is Portia's speech about "the quality of mercy".  Critic Harold Bloom listed it among Shakespeare's great comedies.

Henry V (play): Henry V is a history play by William Shakespeare, believed to have been written around 1599.  It tells the story of King Henry V of England, focusing on events immediately before and after the Battle of Agincourt (1415) during the Hundred Years' War.  In the First Quarto text, it was entitled "The Cronicle History of Henry the fift", which became "The Life of Henry the Fifth" in the First Folio text.

The Boys from Syracuse: The Boys from Syracuse is a musical with music by Richard Rodgers and lyrics by Lorenz Hart, based on William Shakespeare's play, "The Comedy of Errors", as adapted by librettist George Abbott.  The score includes swing and other contemporary rhythms of the 1930s.  The show was the first musical based on a Shakespeare play.  "The Comedy of Errors" was itself loosely based on a Roman play, "The Menaechmi, or the Twin Brothers", by Plautus.

Supporting paragraphs: Le piccole storie Julius Caesar (play)
Answer: Julius Caesar