Ishtar

Ishtar is the Assyrian and Babylonian version of the fertility goddess, sharing local goddess space with the Sumerian Inanna, and Semitic goddess Astarte (Ashtoreth in Hebrew). Though each goddess had local flair, they largely reflected a similar view of the goddess and even shared many specific myths of her doings. In addition to her role as a fertility goddess, she was also the war goddess as well as identified with the planet Venus.

The Epic of Gilgamesh describes her as a petulant and spoiled brat said to have killed or transformed her mortal lovers into beasts. Once Gilgamesh refuses to be Ishtar's next sex toy, she sends against him the Bull of Heaven but not before threatening other gods not very supportive of Ishtar's actions to open the gates of Hell/the Underworld and having the dead outnumbering the living (yes, sounds very familiar). Remember that the Underworld hath no fury like a goddess scorned.

In she attempts the same stunt on her other descent to the Underworld in order to be able to enter there. While it works she is considerably less lucky once inside, first getting to go skyclad and later on her sister the goddess ruler of such place, being not happy at all for the former's attempt to become also Queen of the Underworld in addition to both Queen of Heaven and Earth.

Ishtar was both the most powerful woman in Sumerian religion and also unwed. She was at times considered more powerful than the most powerful god; Enki. Her rituals consisted of the cross-dressing of cult personnel, rituals "imbued with pain and ecstasy, bringing about initiation and journeys of altered consciousness; punishment, moaning, ecstasy, lament and song, and participants exhausting themselves with weeping and grief."

Ishtar was often honored in the form of sacred prostitution, and widely derided, or rather a syncretic combination of her with the goddess Astarte, by prophets as Jeremiah in the Bible as a pagan icon, and a really terrible movie.

Some mythology experts have claimed she was imported in the Greek pantheon as either or at least her Semitic equivalent Astarte, and parts of her cult were incorporated into Athena's one even if the latter was certainly not as petulant and a spoiled brat as the former.

Legacy
Centuries after Ishtar faded out in relative obscurity, she was mixed in with the Easter festivity by Alexander Hislop in his book  because the two names sound similar. This is rejected by modern scholars as a good pile of manure. . She has also ended up being present in Neopaganism, even if that's often a theme park version that has her more masculine elements (warfare, etc.) exchanged with others such goddess originally lacked (mother and marriage), and also in popular culture, often paired with her sister Ereshkigal and considered an useless goddess.