Isis was a major goddess in ancient Egyptian religion whose worship spread throughout the Greco-Roman world. Originally, she played a limited role in royal rituals and temple rites, although she was more prominent in funerary practices and magical texts. She was usually portrayed in art as a human woman wearing a throne-like hieroglyph on her head.

Isis was often characterized as a moon goddess, paralleling the solar characteristics of Serapis. She was also seen as a cosmic goddess more generally. Various texts claim she organized the behavior of the sun, moon, and stars, governing time and the seasons which, in turn, guaranteed the fertility of the earth. These texts also credit her with inventing agriculture, establishing laws, and devising or promoting other elements of human society.

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