The phrase false god is a derogatory term used in Abrahamic religions to indicate cult images or deities of non-Abrahamic Pagan religions, as well as other competing entities or objects to which particular importance is attributed. Conversely, followers of animistic and polytheistic religions may regard the gods of various monotheistic religions as "false gods", because they do not believe that any real deity possesses the properties ascribed by monotheists to their sole deity. Atheists, who do not believe in any deities, do not usually use the term false god even though that would encompass all deities from the atheist viewpoint. Usage of this term is generally limited to theists, who choose to worship some deity or deities, but not others.

Paganism is a term first used in the fourth century by early Christians for people in the Roman Empire who practiced polytheism, or ethnic religions other than Judaism. In the time of the Roman Empire, individuals fell into the pagan class either because they were increasingly rural and provincial relative to the Christian population, or because they were not milites Christi. Alternative terms used in Christian texts were hellene, gentile, and heathen. Ritual sacrifice was an integral part of ancient Graeco-Roman religion and was regarded as an indication of whether a person was pagan or Christian. Paganism has broadly connoted the "religion of the peasantry".