Kilian Flasch was born at Retzstadt, in the Main-Spessart district of Bavaria, to Andreas and Anna Margareta Flasch. One of ten children, he was his parents' fourth child and second son; he was the only son who survived infancy. He was raised on his family's farm and received his early education at neighboring schools. In 1847, his family sold their farm and immigrated to the United States, settling in Fond du Lac, Wisconsin. Flasch entered the College of Notre Dame in South Bend, Indiana, and continued his studies at St. Vincent Seminary in Latrobe, Pennsylvania. In 1856, he returned to Wisconsin and enrolled at the newly opened St. Francis Seminary in Milwaukee. He completed his studies at St. Francis, where he was a member of the first graduating class.
Priesthood and ministry
Flasch was ordained to the priesthood by Bishop John Henni on December 16, 1859. He celebrated his first Mass at the chapel of the School Sisters of Notre Dame, of which three of his sisters were members, in Milwaukee the following Sunday. His first assignment was as pastor of St. Stephen Church in New Coeln, which included the mission of St. James Church in Oak Creek. From 1860 to 1863, he served as the first resident pastor of St. Louis Church inCaledonia. In October 1860, Flasch was appointed professor of moral theology and master of discipline at St. Francis Seminary. He remained at the seminary until the spring of 1865, when he became a chaplain and instructor at a convent of the Franciscan Sisters of Perpetual Adoration in Jefferson due to ill health. He briefly resumed his duties at the seminary before being named pastor of St. Mary's Visitation Church in Elm Grove in May 1867. During his seven-year tenure, he constructed a new church building and rectory, and ministered to an orphanage. He returned to St. Francis Seminary in November 1874, where he resumed his post as professor of moral theology in addition to becoming spiritual director. From 1879 to 1881, he served as rector of the seminary.
On June 14, 1881, Flasch was appointed the second Bishop of La Crosse by Pope Leo XIII. He received his episcopal consecration on the following August 24 from Archbishop Michael Heiss, with Bishops Francis Krautbauer and Rupert Seidenbusch serving as co-consecrators, at the chapel of St. Francis Seminary. He was installed on September 1. Flasch made his first ad limina visit to Rome in 1883. He attended the Third Plenary Council of Baltimore in 1884, serving as a member of the Committee on Schools. An outspoken supporter of Catholic education, he established 36 new schools during his tenure and, at the Plenary Council, unsuccessfully sought to require Catholic parents to send their children to parochial schools. However, he originally opposed creating a national Catholic university but later served on the Board of Trustees for the Catholic University of America. He presided over the second diocesan synod of La Crosse in 1887, and created over 60 new parishes. Because of his poor health, Flasch traveled to Chatawa, Mississippi, in March 1891 for a change of climate. The trip proved unsuccessful and he returned to La Crosse, where he died two months later at age 60. He was originally buried in the Catholic Cemetery Chapel, but his remains were later transferred to the Cathedral of St. Joseph the Workman.
