I want to test the ability of students to read a passage and answer questions about it. Could you please come up with a good question for the passage "Christianity is the most widely practised religion in Galicia, as it has been since its introduction in Late Antiquity, although it lived alongside the old Gallaeci religion for a few centuries. Today about 73% of Galicians identify themselves as Christians. The largest form of Christianity practised in the present day is Catholicism, though only 20% of the population described themselves as active members. The Catholic Church in Galicia has had its primatial seat in Santiago de Compostela since the 12th century."? 

When did the Gallaeci religion cease to be the main religion in Galicia?