The myth of Cancer is primarily linked to the second labor of Hercules. Sent by the goddess Hera to distract the hero during his fight with the Hydra, the crab latched onto Hercules' foot. Though it was crushed, Hera placed the crab's image in the sky for its service, creating the constellation.

In other traditions, the constellation was associated with a gate through which souls descended from heaven to be born on Earth, emphasizing its connection to nurturing, home, and the beginning of life.

Known to ancient Babylonian astronomers as "The Crayfish" or "The Turtle," it was seen as a gate of the sun. The Greeks later solidified its identity as a crab.

The constellation is relatively faint but houses the famous open star cluster, Praesepe (the Beehive Cluster), visible to the naked eye. For millennia, this fuzzy patch was used as a weather predictor by sailors and farmers.

In astrology, Cancer's history as a nurturing, protective, and tenacious creature translated into the personality traits of those born under its sign. Ruled by the Moon, it became the sign of emotion, intuition, memory, and domesticity.

Its cardinal quality marks it as a initiator of seasons (the Summer Solstice once occurred in Cancer), representing the beginning of summer and a time of growth and nurturing—key themes for this zodiac.