Legend has it that in the late tenth century, the pagan Russian prince Vladimir the Great sent envoys across the world to discover and bring back all of the major world religions for the Russians to choose from.
Eighty-four percent of people who do not identify with a religion said the religious beliefs of their spouse were not important in their decision to marry.
So the charges were impiety, which is to say not believing in the gods of the state and also sort of promoting his irreligiosity to others, and corrupting the youth.
None of the astronomers were irreligious men; all of them made a point of magnifying God through his works; a form of science which did their religion no credit.
Religiously unaffiliated people have grown in numbers in recent decades, and according to Pew Research, they now make up about 16% of the global population.