There was dechristianisation in France during the French Revolution because of the state of the church. It began with attack on church corruption and the wealth of the higher clergy. During the two year period – 1793 to 1794, anti – clericalism grew more violent than any modern European history.
Church authorities were suppressed, the catholic monarchy was abolished and nationalized church property was suppressed. Thousands of priests were exiled and hundreds of them were killed. The Christian calendar was also replaced with one starting from the date of Revolution and festivals of Liberty.
The public reclaimed the power, massive amount of land and money held by the Catholic Church in France.
There was a brief but nasty wave of dechristianisation in France during the French Revolution. Various separate policies angered the populous. But the revolt was against the established power of the catholics.
The Cult of Reason of 1792 was set up to counter catholic teachings. But Napolean's influence was great. A year-long negotiation between government officials and the new Pope, Pius VII, paved to the way for the Concordat of 1801.
This formally ended the dechristianisation period and established rules to underpin how the Roman Church and the French State could peacefully coexist.