In 1866 the German families who had settled in Florissant petitioned the Most Reverend Peter R. Kenrick, Archbishop of St. Louis for permission to establish a parish where German would be spoken. Approval was granted for the establishment of the Church of the Sacred Heart of Jesus. The founding parishioners acquired a plot of land consisting of 2 1/2 acres bounded by St. Denis, Jefferson, St. Louis and St. Jacques Streets. The first building constructed was the school. It was located on the corner of Jefferson and St. Louis streets and opened in September of 1866. The upper floor of the two story building was used as a convent. The lower floor contained two classrooms. The Sisters of St. Joseph were instructors in the school until 1877. At that time the Sisters of the Most Precious Blood came to Sacred Heart.
The cornerstone for the church was laid in June of 1866. The church was completed on September 14, 1867, the feast of the Exaltation of the Holy Cross. On October 6, 1867 Sacred Heart Church was blessed by the famous missionary, Father Pierre Jean DeSmet, S.J. Father Ignatius Panken, S.J. was named the first Pastor of Sacred Heart and served one year. He was succeeded by Rev. Ignatius Peuckert, S.J. Between 1867 and 1872 the interior of the church was completed.
Because of the increase in pupils and the general condition of the school, plans for a new school were drawn up in the fall of 1888. The new school was located at the corner of St. Denis and Jefferson Street. The school was solemnly dedicated on November 28, 1889. The previous school remained as a convent for the Sisters.
By the year 1892 the church was in hazardous condition and it was necessary to take the old church down and rebuild it. All but the steeple was rebuilt. The new church was completed in November of 1893. It was constructed in the classic Gothic style in the form of a cross with a double cross-bar. It measured 155 feet long, 62 feet wide and reached to 43 feet at its highest point. The sanctuary was 28 feet deep and 30 feet wide and was separated from the remainder of the church by a triumphal arch. Stained glass windows were placed down the sides of the church and around behind the altar.
In 1903 the convent burned to the ground. Plans began for another convent and the building was completed the following September. This building still stands at the corner of St. Louis and Jefferson Street. In 1952 it became necessary to build a new school. The corner stone was laid on March 23, 1952. It faced St. Louis Street. In 1957 the Missouri Province of Jesuits petitioned Cardinal Ritter to have the Jesuits relieved of parish duties at Sacred Heart. Ninety one years of Jesuit presence at Sacred Heart came to an end.
In 1958 major repairs and renovations were made to the church building. A terrazzo floor replaced the wooden one. A new high altar replaced the wooden one which was beyond repair. New side altars were also secured. New art glass windows were installed and over the front doors of the church were erected stones carved with symbols of the Holy Trinity. Renovations were again needed in the early 21st century. The heating and air conditioning systems were refurbished, lighting was replaced, and the interior was painted. Exterior wooden doors and exterior lighting will be installed soon. The church stands today, a building rich in history having provided worship space and welcome for many, many families throughout its history.