St. Louis' was the first congregation organized west of Rochester, and the first in the present Diocese of Buffalo. The Rev. Stephan Badin sojourned in Buffalo six weeks with Mr. Louis Lecouteulx before returning to his own mission in Kentucky. This was in the winter of 1828 - 1829, and Father Badin said Mass for the Catholics several times during his visit, in the court house or in the home of Mr. Lecouteulx. Mr. Lecouteulx owned several tracts of land in Buffalo, and Father Badin persuaded him to donate the plot, corner Main and Edward Streets, as a site for a church. The deed dated January 5, 1829, was drawn up and sent to Bishop Dubois as a New Year's gift.
The Bishop came to Buffalo, July of the same year, sang high Mass in the court house and dedicated the ground to the purposes designated by the donors. The Bishop celebrated a solemn high Mass on this occasion in the court house, at which there were more than eight hundred persons present. This was the first time that such religious solemnity had been witnessed in Buffalo, and it made a deep impression on both Catholic and Protestant.
At 4 o'clock in the afternoon another ceremony, strange to this part of the world, took place. The Bishop vested in solemn Pontificals, and, proceeded by an immense throng, left the court house in procession to bless the new cemetery. It was a strange and inspiring sight to witness this procession, headed by four old men who recited the Rosary in German, while English, and French and German responded in his own tongue.
A delegation of Catholics called upon the Bishop and begged him to send them a priest. The Rev. John Nicholas Mertz came to Buffalo shortly after, and he was the first resident priest of the incipient St. Louis' congregation. He secured a little log house on the west side of Pearl Street, midway between Court and Eagle Streets, where he dwelt for some years. He rented a small frame building, which had at one time served as a meeting house for Methodists, situated in an open space between Pearl and Main Streets; and here the saintly old man organized the first Catholic congregation of Buffalo. Here they had vespers occasionally, sung by an impromptu choir, to the accompaniment of a small reed organ placed on the floor near the door of the building. Here they had the first school also, where every afternoon the younger ones could learn to read and write and spell.
Many Catholics came to Buffalo in the next three years: and Father Mertz resolved to erect a more commodius structure, on the site donated by Mr. Lecouteulx. The parishoners were poor and could not donate money, but they gave their time and labor to the work; and they hewed huge timbers in the forest on Delevan Avenue and drew them in with their ox teams, and placed them in position for the frame work of their church. The interstices were filled in with a primitive sort of mortar composed of straw and clay.
Father Mertz had brought some money from Europe, and some of this he used to purchase whatever was needed that his people could not supply. He also brought a bronze tabernacle with him, which had a symbolic figure of the "Lamb" on the upper portion of the door. It was from this that the church derived its name, and it was called the "Lamb of God." The little church was begun in 1830. The corner-stone was laid July 8, 1831; but such slow progress was made that it was not ready for services until the spring of 1832. No provision was made for heating the church in cold weather. Artificial heating was considered a luxury, which few of the early churches enjoyed.
In 1835 Father Mertz was fast failing under the weight of years and the burden of his ever increasing labors; so the Bishop sent him an assistant in the person of the Rev. Alexander Pax. Father Mertz practically transferred the responsibility of the parish to Father Pax, and the next summer he proceeded to Europe for a well-earned rest.
Father Pax took full charge of the church, and he planned to build a large brick church around the form of the old rough cast structure. He labored under many difficulties, and against much opposition, but he triumphed and he saw the completion of his work in 1843. Then he resigned his position and returned to his native land. This church was later enlarged, and was totally destroyed by fire on the evening of March 25, 1885. Not disheartened by the great loss, the congregation, under the direction of Rev. Joseph Sorg, immediately started a frame structure, which was completed in less than three weeks. The pastor and people next planned the magnificent structure which now adorns the handsome property. The corner-stone was laid May 29, 1886, and the first religious service was held in the church August 25, 1889, when the building was blessed . The following pastors labored in St. Louis' Church: Rev. John Nicholas Mertz, November, 1829, to June, 1836; Rev. Alexander Pax, August, 1836, to March 19, 1843; Rev. Francis Guth, September 1, 1844, to September, 1855; Rev. William Deiters, September, 1855, to June 11, 1861. Priests from St. Michael's and St. Mary's attended during vacancies. Rev. J.E. Moshall, September, 1861, to February, 1862; Rev. S. Schoulepnikoff, January, 1864, to August, 1867; Rev. J.M. Sorg, August, 1865, to September, 1888; Rev. P. Hoelscher, D.D., to December 27, 1916. Dr. Hoelscher added greatly to the beauty of the building by interior ornamentation and handsome furnishings. Miss Emma Lang left $16,000 for a marble altar, which was placed in position in the sanctuary of the church.
Monsignor Paul Hoelscher died, December 23, 1916, and was succeeded by the Rev. Henry Laudenbach in January, 1917.
Fire again threatened the church in 1921, but the damage was soon repaired and the church was redecorated. The church was consecrated in 1912. The rectorship of St. Louis' is one of the irremovables.
Evils had arisen from the trustee system, the trustees claiming the right to appoint or disapprove at will, all officials of the parish, even including the pastor. In the first synod of the diocese, held in New York, August, 1841, a decree was passed defining the powers of pastors and trustees. Bishop Hughes ordered the decrees to be read in all the churches of the diocese.
At a meeting of the trustees of Saint Louis Church held, shortly after the decrees of the synod were read in the church, they decided not to comply with the new regulations. This insubordination caused a bitter and long drawn out controversy, filled with accusations and incriminations which finally terminated in an interdict which closed St. Louis' Church for two years.
Rev. Thomas Donohue, D.D., History of the Diocese of Buffalo (Buffalo, New York: The Buffalo Catholic Publication Co., Inc., 1929), p. 195 - 198.