In 1659 Pope Alexander VII instructed Bernini to build the church, to replace the old church of St. Nicholas. Bernini then also completed the landscaping with the square and the fountain. The church has a facade that sweeps upwards and ends with a dome that rests on Doric pillars. The Greek cross interior is decorated with paintings by Pietro da Cortona, del Raggi and Carlo Maratta. The church is located in the extraterritorial area, adjacent to the areas of the Papal Palace and the adjoining Villa.