When Was Religious Syncretism First Used?

The first known use of syncretism was in 1618.

When did religious syncretism start?

The fusion of cultures that was effected by the conquest of Alexander the Great (4th century bce), his successors, and the Roman Empire tended to bring together a variety of religious and philosophical views that resulted in a strong tendency toward religious syncretism.

Who came up with syncretism?

In the 16th century, the Mughal emperor Akbar proposed a new religion called the Din-i Ilahi ("Divine Faith") that was intended to merge some of the elements of the religions of his empire and thereby reconcile the differences that divided his subjects.