Greek Mythology
In Greek Mythology, Hera is the queen of Mount Olympus. She also happens to be both wife and sister of Zeus as well.
God of War
Hera is mentioned in the first God of War as a part of puzzle, where the player has to locate the "Hera's Necklace". She is the wife of Zeus, but never appeared in any other form in a God of War media to date. Hera will probably make an appearance in God of War III, most likely as a boss, since she has a voice actress next to her name on IMDb.