Well, this famous Prince of Denmark may be more of a fictional character than a mythological one, but there's no denying he's legendary. Many have theorized that Shakespeare may have been inspired by the Orestes myth (and/or the Greek tragedies about him) when he created his most famous character. There's no getting around that there are tons of parallels between these two moody princes.
Like Orestes, Hamlet is out to avenge the murder of his father. However, both of these guys have to do some serious thinking before they do it. They differ a bit in that Hamlet's father was killed by his uncle instead of his mom. In some versions of Orestes' story, though, Aegisthus (who is Agamemnon's cousin) either plays a big part in the murder or does it himself.
Another similarity is that both Hamlet's and Orestes' moms move on pretty quickly after their husbands die. Gertrude, Hamlet's mom, marries her former brother-in-law Claudius shortly after her husband is buried. Though Gertrude has nothing to do with the murder of her husband, like Clytemnestra, her ability to hop in bed with another member of the family so quickly only adds fuel to her son's angst.
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