In a developer diary, Europa Universalis 4 project lead Thomas Johansson discusses the role of religion in the upcoming strategy title.
As in the real world, explains Johansson, different countries will start out having different religions, and may potentially have sub-regions that in turn have different faiths. Leaders must either spread the country's main religion to these outlying areas, or must try and manage a kingdom where different religions coexist.
Different religions also have different gameplay mechanics, says Johansson. Muslim countries will gain Piety when warring against "heathen" religions, which will empower their armies in the field. However, lower levels of Piety will enable a ruler to shake off the theocracy in order to pursue technological advancement. A Catholic ruler, on the other hand, will start with a Europe unified under one common faith, but will find themselves facing the Reformation and rise of Protestantism come the advent of Martin Luther.
Europa Universalis 4 hits Windows PC this August.