thousands of years in all aspects of life (money, politics, gender roles, etc.). Too bad. What a waste of time and energy over something that can be changed as easily as the direction of the wind yet is considered so important that millions of lives are lost over it due to wars, money, slavery, etc in so many societies and cultures.
The artists worked for the religious leaders whoever they were at the time. The popes would commission artists as Madison Ave does today...it was paid for. The artists may not have done it as much as a call from their favorite religion of choice (few had a choice) but as a way, often the only way, to make a living. Artists were, and still are, a dime a dozen and finding work it tough. A pope or rich person connected to the church was often the only source of income for an artist. Read about Caravaggio. He was persecuted and cheated of his commissions by "priests" and their politics. Their work was dictated by the current religion in power and was often not a choice.