Hercules encountered many people in his travels and labors. For convenience, I've listed the following as friend, family, or enemy of Hercules. As usual, such labels are simplistic. This list of people in Hercules' life is based on the Loeb edition of the Library of Apollodorus, a 2nd Century B.C. Greek scholar, who wrote a Chronicles and On the Gods. It is thought that the Library (Bibliotheca) was written by someone a few centuries later, but it is still referred to as the Library of Apollodorus or Pseudo-Apollodorus.
Also see the Apollodorus Concordance for names and places in Apollodorus' account of the Labors of Hercules.
Alcmene (Alcmena) - Family of Hercules
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Alcmene was the mother of Hercules. She was the grand-daughter of Perseus and the wife of Amphitryon, but Amphitryon killed her father, Electryon, by accident. The marriage wasn't to be consummated until Amphitryon had avenged the death of Alcmene's brothers. On the night after this was accomplished, Zeus came to Alcmene in the guise of Amphitryon with proofs of the revenge. Later, the real Amphitryon came to his wife, but by this time she was pregnant with her first son, Hercules. Amphitryon fathered Hercules' twin brother, Iphicles. [Apollodorus 2.4.6-8]
Pelops is given as Alcmene's father in Eur. Herc. 210ff.
Rhadamanthys married Alcmene after Amphitryon died. [Apollodorus 2.4.11]
Amazons - Friends and Enemies of Hercules
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Amphitryon - Father of Hercules
Amphitryon, a grandson of Perseus and son of King Alcaeus of Tiryns, was the step-father of Hercules and father of his twin brother Iphicles. He accidentally killed his uncle and father-in-law, Electryon, and was driven out by another uncle, Sthenelus. Amphitryon took his family to Thebes where King Creon purified him. [Apollodorus 2.4.6]Antaeus - Enemy of Hercules
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Argonauts - Friends of Hercules
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Augeas - Enemy of Hercules
King Augeas of Elis offered to pay Hercules for cleaning out his stables in a day. Hercules diverted the Alpheus and Peneus riversto clean the years' worth of filth, but the king refused to pay. Augeas' son Phyleus testified on behalf of Hercules when his father denied he had promised to pay. Hercules later returned and got revenge. He also rewarded Phyleus by installing him on the throne. [Apollodorus 2.5.5]Autolycus - Friend of Hercules
Autolycus was the son of Hermes and Chione. He was the ancient prince of thieves who taught wrestling to Hercules.Cacus - Enemy of Hercules
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Cacus is a Roman enemy of Hercules. Livy says that when Hercules passed through Rome with the cattle he had taken from Geryon, Cacus, a thief who lived in a cave on the Aventine, stole some of them while Hercules was napping. Hercules located the missing cattle when the stolen ones lowed and the ones he still had in possession, replied. Hercules then killed Cacus. In other versions, Cacus is a horrible cannibalistic monster.
Castor - Friend of Hercules
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