Robert Louis Prazan, O.P., was born on September 5, 1936, in Chicago, Illinois, the oldest of the two children of Louis J. Prazan and Lillian Mary Rasch. He attended St. Leonard Grammar School, Berwyn, Illinois, and Fenwick High School, Oak Park, Illinois. Before entering the Dominican novitiate at St. Peter Martyr Priory, Winona, Minnesota, in August 1956, he attended Loras College, Dubuque, Iowa, for two years.

He was given the religious name, Ceslaus, and made first profession at Winona on August 31, 1957. He was then assigned to St. Thomas Aquinas Priory (Dominican House of Studies), River Forest, Illinois, for philosophical studies (1957-60), earning a bachelor's in philosophy degree. After profession of solemn vows on August 31, 1960, he went to Dubuque, Iowa, for theological studies at Aquinas Institute, School of Theology (1960-64). There on April 15, 1963, Bishop George J. Biskup ordained him a priest in the chapel of St. Rose of Lima Priory.

After completion of basic studies Father Prazan was assigned to the foreign missions in Nigeria, West Africa, where he was to spend the next twenty-two years of his priestly ministry. After a brief stay in Gusau, Zamfara State, he was assigned as an assistant pastor at St. Dominic Parish, Yelwa, Northern Nigeria, where he spent the next nine years (1965- 74) engaged in pre-evangelization work among the Dukkawa people. In the book The Dukkawa of Northwest Nigeria he tells the story of these people. Then for three years (1974-77) he served as assistant pastor at St. Vincent Ferrer Parish, Malumfashi, Northern Nigeria, among the Maguzawa, an ancient Hausa-speaking people. In 1977 he began the third phase of his missionary work which was to continue until his return to the United

States in November 1986. During this time, he was stationed at Our Lady of Fatima Parish, Gusau, Zamfara State, and devoted his efforts to full-time preaching and writing in Hausa. To help eradicate illiteracy he produced a very popular aid for teaching Hausa-speakers to read - Karatu: "Rashin sani ya fi dare duhu". For English-speakers learning the Hausa language he wrote Hausa Hints. Among his other writings were two small booklets on the miracles of Jesus and a booklet on the rosary. In addition to the written word he extended his preaching by producing tapes.

In November 1986, two years after Nigeria had become an independent Province, Father "Ces" returned to the United States, and spent some months in reorienting himself to his native country. He spent six months in campus ministry at South Dakota State University, Brookings, South Dakota, and then explored preaching team ministry in McAllen, Texas. While providing temporary supply help at Our Lady of Pompeii Parish, Tickfaw, Louisiana, Father Prazan found the second love of his priestly ministry. From March 1988, until his death he served the people of this parish.

In early summer of 1997 "Ces" was diagnosed as having a malignant inoperable tumor in his chest. Chemotherapy and radiation treatments followed. After a brief remission, the cancer began to spread and, in spite of additional chemotherapy treatments, it continued to ravage his body, but not his spirit. He continued his pastoral work at Our Lady of Pompeii parish as long as he was able. His conditioned worsened and on the afternoon of July 5, 1998, because of severe difficulty in breathing, he was rushed to the hospital in Hammond, Louisiana. Efforts to revive him were futile. His funeral Mass was celebrated at his beloved parish on July 8, 1998, with burial in the Dominican plot at Rosaryville, Louisiana.