Standing as the oldest church structure in continuous use, the Cathedral of Immaculate Conception was built in 1860. The Cathedral is the seat of Catholicism in northern Indiana. The first major portion of the cathedral square was acquired and purchased by Father Stephen Badin, in 1831. The remaining land was obtained by Father Julien Benoit, who happened to also be the chief architect and first rector of the cathedral. The cornerstone was laid June 19, 1859 and dedicated on December 8, 1860.

The Diocese of Fort Wayne was established in 1857; John H. Luers was the first bishop.  When this movement occurred, the idea to build a large Cathedral was created. The 180-by-80-foot church that hosts two steeples cost a mere $46,000 to construct. In December of 1860 when the church was completed, then the largest church in the state, it was dedicated to the Immaculate Conception by Bishop Luers.