<human>:  When did the process of secularization begin?
<bot>: The process of secularization began with the Reformation, which started in 1517. The Reformation was a religious movement that took place in Europe in the 16th century, and it was a reaction to the Catholic Church. The Reformation split the Catholic Church into two groups: the Roman Catholic Church and the Protestant Church. The Protestant Church is the one that you belong to.