Polytheism
Polytheism means believing in many gods. A person that believes in polytheism is called a polytheist. A religion with polytheism can be called a polytheistic religion.
Polytheism is well documented in historical religions of classical antiquity, especially those of Ancient Greeks and Ancient Rome. Other ancient peoples who were polytheists were Germanics, Turkic peoples, Ancient Egyptians, Celts, and the Norse.
There are various polytheistic religions that are practiced today such as Sanamahism (Meitei paganism), Tengrism, Shinto, Chinese folk religion, Thelma, Wicca, Druidism, Taoism, Asatru and Candomblé.
Polytheistic religions usually include a set of stories about the gods, which is called mythology.
The opposite of polytheism is monotheism, which is the belief in only one god and is practiced by Judaism, Christianity, Islam, Sikhism, etc.