In Greek mythology, Pentesileia was an Amazon queen, daughter of Ares and Otrera, and sister of Hippolyta, Antipope and Melanippus. The Pseudo-Apolodorus tells how Pentesileia entered the Trojan War: Pentesileia and her sister Hippolyta were hunting when the latter accidentally killed Hippolyta with her spear.
The accident caused Pentesileia so much pain that she felt like dying, but as an Amazon warrior she had to do it in battle. In this way she was easily persuaded to enter the Trojan War.
Some writings narrate Pentesileia's entry into the Trojan War:
"Those were the funeral games of Hector. And now came an Amazon, the great daughter of the heart of man - beheaded Ares."
"Now they say that it was Pentesileia of the Amazons to gain distinction of bravery, and that for the future of the race diminished more and more and then lost all her strength, consequently in later times, whenever any writers recount her bravery, men consider the ancient stories about the Amazons to be fictitious tales." (Diodorus Siculo, ii. 46).
According to most stories Pentesileia was killed by Achilles, who fell in love with her after the death of the Amazon and killed Tersites for mocking him.
According to the tragedy Pentesileia by Heinrich von Kleist, which is translated into Portuguese by Roberto Machado and Robert Weisshaupt, it was Pentesileia who killed Achilles, and killed herself soon after, because they loved each other.