As with many other Inuit groups, Copper Inuit religion was more concerned with the here and now than with an afterlife. Most important was the relationship between humans and the spirits of the animals upon which humans depended for food. It was essential that the proper rituals be followed, so as not to offend these spirits, who are perceived as being much like humans. An animal spirit that had been offended through the violation of a taboo or the omission of an important ritual might decide to take revenge upon the group as a whole. Illness, starvation, or some other disaster could result. Copper Inuit observed a number of taboos which were believed to be important to maintaining good relations with the spirit world. A number of observances were related to the separation of land animals and sea animals. Copper Inuit were prohibited for cooking products of the land and sea in the same pot. Nor could they place seal meat next to caribou meat on the sleeping platform of the snow house.  Most pronounced was the prohibition against sewing caribou skin clothing during the early winter. All winter clothing had to be prepared in the fall, at the gathering places, and completed before the move to the sealing grounds on the sea ice.

In addition to believing in the spirits of animals and the shades of deceased humans, the Copper Inuit subscribe to a world inhabited by wondrous and often dangerous creatures dwarfs, giants, and Caribou people. They believed in a sea goddess (known as Sedna in other regions) who control the animals of the Seas. Arnapkapfaaluk, or 'big bad woman,' was not a benevolent goddess looking out for human beings: when offended by the violation of a taboo or some indiscriminate action, she would withhold the seals upon which people depended for survival.

Animal spirits

William Kuptana: The custom of the Eskimos is that when they take part in a hunt and make a kill, all who hunted the animal must participate in the cutting and sharing of the carcass. Those who do not follow that custom embarrass the animal spirit; therefore, it is believed that the non-participant will be hunted himself.

Death was not accompanied by elaborate ceremony. In Winter, the body was usually left behind and it's no house, while in summer, the body was wrapped in skins and left on the time go. The concept of an afterlife was not well developed. Jenness reported that it was definitely not viewed as a land of joy and plenty, but a "big and gloomy realm where, even if want and misery are not found (and of this they are not certain), joy and gladness at least must surely be unknown." (Jenness 1922: 190)

Shamans (angatkut) Served as important intermediaries between humans in the spirit world. Shamans provided a number of essential functions. They could act as healers, in the event of an illness, or could determine what taboos were violated When Animals became scarce. They were also believed to have powers for controlling the weather and warding off evil spirits. The shaman, acting as an intermediary, could communicate with animal spirits, often doing so with the aid of a spirit helper or familiar. Most angatkut claimed to have more than one helper. Jenness met one Copper Inuit shaman, Uloksak, who claimed to have a white man, a polar bear, a wolf, and a dog as helping Spirits. Shamans could be either male or female, but no matter what their gender they were expected to have some kind of visionary experience whereby a spirit helper revealed itself to the future angatkut. In their shamanistic performances, shamans may have relied upon ventriloquism and other dramatic acts to impress their audiences and demonstrate their powers. Shamans by definition are neither good nor bad. Some angatkut developed reputations for kindness and generosity;  others were greatly feared and used their powers to gain advantage over others.