Rev. Pierre DeSmet (1801-1873), born in Belgium, came to America in 1821, joined the Jesuit Society, and began work with Indians. He established 16 treaties, crossed the ocean 19 times, and traveled 180,000 miles in charitable service to Indians who knew him as “The Sincerest Friend.” On July 5, 1840, before 2,000 Indians, trappers, and traders, he offered the first Holy Mass in what is now Wyoming on an altar of native stone decorated with wild flowers. In his own words, it was “a spectacle truly moving to the heart of a missionary” to see this immense family of many different tribes prostrate themselves in equal humility before the “Divine Host.” On July 4, 1940, the 100th anniversary of that first Mass, a Pontifical high mass was offered by the Most Rev. Bishop McGovern, assisted by more than 30 priests and attended by about 2000 people.