In ancient Roman religion, Concordia is the goddess who embodies agreement in marriage and society. Her Greek equivalent is usually regarded as Harmonia, with musical harmony a metaphor for an ideal of social concord or entente in the political discourse of the Republican era. She was thus often associated with Pax ("Peace") in representing a stable society. As such, she is more closely related to the Greek concept of homonoia, which was also represented by a goddess.

In Greek mythology, Harmonia is the goddess of harmony and concord. Her Roman counterpart is Concordia. Her Greek opposite is Eris, whose Roman counterpart is Discordia.