Hera, in ancient Greek religion, a daughter of the Titans Cronus and Rhea, sister-wife of Zeus, and queen of the Olympian gods. The Romans identified her with their own Juno. Hera was worshipped throughout the Greek world and played an important part in Greek literature, appearing most frequently as the jealous and rancorous wife of Zeus and pursuing with vindictive hatred the heroines who were beloved by him. She also famously drove Hercules mad, causing him to kill his wife and children, leading to the 12 penitential labours forced on Hercules. From early times Hera was believed to be the sole lawful wife of Zeus; she soon superseded Dione, who shared with him his ancient oracle at Dodona in Epirus.

In general, Hera was worshipped in two main capacities: (1) as consort of Zeus and queen of heaven and (2) as goddess of marriage and of the life of women. The second sphere naturally made her the protectress of women in childbirth, and she bore the title of Eileithyia, the birth goddess, at Árgos and Athens. At Árgos and Sámos, however, Hera was even more than queen of heaven and marriage goddess. She was patron of those cities, which gave her a position corresponding to that of Athena at Athens. Although her Argive ritual was markedly agricultural, she also had a celebration there called the Shield, and there was an armed procession in her honour at Sámos. This conception resulted from the breadth of functions attributed to the patron deity of a Greek state: a city goddess must be chief in peace and war alike. The animal especially sacred to Hera was the cow. Her sacred bird was first the cuckoo, later the peacock. She was represented as a majestic and severe, though youthful, matron.

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