This week marks the 177th anniversary of the first Catholic Mass ever conducted in the Cowboy State. July 5, 1840, Father Pierre De Smet presided over the mass during the annual Green River Rendezvous at Horse Creek in Sublette County, near the present-day town of Pinedale.

The Belgian-born De Smet came to America at the age of 20 and eventually became a Catholic missionary to Indian tribes througout the west. In 1840, he followed a fur trading company through Wyoming, stopping along the way at Red Buttes near Casper and long enough to carve his name into Independence Rock.

By July 5th, De Smet and his party had arrived at the Rendezvous, where a handful of fellow Catholics observed mass and took communion.

De Smet returned to Wyoming several times, becoming a widely respected advisor to tribes across the region and was given the nickname "Black Robe".

During his final visit to the area in 1851, his party named a lake in his honor 16 miles north of present-day Buffalo, Wyoming. Twenty years later, after the railroads brought European settlers, De Smet served on the Board of Indian Commissioners and was assigned to supervise four reservations.

Catholicism spread slowly throughout the territory. Most of the early churches across the state were established by protestants. Finally, nearly 50 years after the first mass was held in Wyoming, the Diocese of Cheyenne was founded in 1887.