This building is unique in that it comprises two interconnecting churches: the old, Saint-Blaise, built in 1714, and the new, Notre-Dame-des-Malades, built in 1931. Saint-Blaise has always inspired intense devotion, not least due to the presence of a 14th century Black Madonna venerated for her miracles.
In the 1920s, a growing local population and seasonal attendance drove the construction of a new building, with Abbé Robert, in charge of the old church, convincing the municipality to provide land for the extension. He consulted the architects Antoine Chanet and Jean Liogier to design the best possible plan, taking account of several key constraints: the need to preserve the old church, to make best use of the small plots of land granted for the new church, and to ensure that the building would blend seamlessly into Vichy's historic centre. The architects opted for a basilica layout with a reinforced concrete construction, the austere exterior contrasting with the rich interior decor by the Mauméjean workshops, making the church an outstanding example of Art Deco religious architecture. The bell tower of Notre-Dame-des-Malades was not completed until 1956.