In 1833 a Bavarian immigrant named John Ruppert purchased half of Section 22 in Pusheta Township, south of Wapakoneta, “and on this land [would be] erected the first church of Petersburg, which was dedicated in honor of the Apostles Peter and Paul.”
Meanwhile, Father Wilhelm Horstman of the Missionaries of the Precious Blood had arrived in the United States in 1831, and immediately began to serve the German-Catholic settlers of west-central Ohio, beginning in Putnam County. A remarkably zealous missionary, Horstman regularly traveled across several counties. Father Horstman first visited the congregation at Petersburg on May 8, 1835. In a subsequent letter to Bishop Purcell, Father Horstman reports that he stayed three days saying Mass, baptizing, etc. The Catholics there were fervent except a few, led by a certain Schimmel, who had been married by a civil magistrate. All the rest were zealous for divine service and planned the buying of a plot and erection of a church for the neighborhood, to be used also as a school – In a priest’s absence they had prayers led by Joseph Klupfel. [The congregation] desires that stone, chalice, etc. be sent them.