To the victor go the spoils…and the right to re-decorate.
In the site where Cordoba’s Mezquita now stands there was once a Roman temple, then a Visigothic cathedral and then a mosque. Rather than re-do the entire edifice in the 13th century when Christian crusaders took over the town, they left the majority of the mosque intact but made a significant alteration. They constructed a Catholic church in its center.