Saints Peter and Paul Cathedral was built between 1905 and 1907 with a temporary facade. James Renwick Jr.'s architectural firm of Renwick, Aspinwall and Russell, W. L. Coulter of New York designed the Classical Revival-style cathedral, rectory, and adjacent chapel. It is believed the design for the cathedral is modeled after Saint John Lateran in Rome, Italy. William Whetten Renwick, nephew of American architect James Renwick Jr., assumed sole responsibility for the completion of the cathedral around 1900, a few years after James's death, and simplified its design. The Indianapolis architectural firm of D. A. Bohlen and Son served as local supervisors for the construction project. The high altar of the unfinished Saints Peter and Paul Cathedral was consecrated on December 21, 1906, and the first Pontifical High Mass at the new cathedral took place on December 25, 1906. Construction of the permanent facade and twin spires was postponed due to a shortage of funds. Bishop Ritter arranged for the completion of the cathedral in 1936, when Indianapolis architect August Bohlen, son of Oscar and grandson of Diedrich Bohlen, supervised construction of the permanent facade, which was designed by Layton (Dick) DeMilt of the Bohlen architectural firm. The permanent facade was also modeled after Saint John Lateran in Rome.