Once Upon A Time there were Women Priests
Vatican unveils restored catacomb with frescoes showing 'female priests'
Women depicted in scenes show they were priests, say activists; they were just praying like everyone else, says Holy See
Newly restored frescoes prove early Christian church had women priests, outlaw Catholic group says
Just Follow the Money
Originially Priests married and had children. Naturally the family business was religion and the physical property of the church. It was natural to pass your "riches" onto your sons who would inherit the Church and the business of collecting monty for the church.
This interferred with Rome's business plan. They wanted the financial proceeds in the supply chain to go back to them not "sons" of the priest.
Hence: a new law that they could not marry solves that problem.