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- Octavia, sister of Octavius, marries Mark Antony when he is widowed in Antony and Cleopatra. Their marriage causes great distress to Antony's lover, Cleopatra.
- Octavius Caesar is one of the Triumvirs, the three rulers of Rome after Caesar's death, in Julius Caesar and Antony and Cleopatra.
- For Old Clifford see Clifford.
- The Duke of Orleans fights on the French side in Henry V.
- For Owen Glendower see Glendower.
- The Earl of Oxford is a staunch Lancastrian, supporting Henry in Henry VI, Part 3, and Richmond in Richard III.
Read more about this topic: List Of Historical Figures Dramatised By Shakespeare