1854 Reciprocity Treaty between the US and Canada comes into effect.
1868 Vigilantes hanged three members of the Asa Moore Gang in Bosler, where some of the gang members owned a bar. One of the gang members, Big Steve Long, asked to leave his boots on, stating: "My mother always said I'd die with my boots on". He was lynched with his boots off.
1871 A gunpowder explosion on the Colorado Central saw 600 kegs of powder explode, but with no injuries.
1919 Robert Russin's statute of Lincoln on the Interstate Highway between Laramie and Cheyenne dedicated. That route was part of the Lincoln Highway at the time, hence the dedication. Attribution: Wyoming State Historical Society.
1929 The Historical Landmark Commission of Wyoming set up an advisory committee to explore acquiring the grounds of Ft. Laramie. Attribution: On This Day.
1931 A Pony Express Historical marker was dedicated at Independence Rock. Attribution: Wyoming State Historical Society.
1969 The football game between the University of Wyoming and BYU that sparked the protest of the Black 14 occurred. Wyoming won the game.
1989 The Contract to build SSBN 742, an Ohio Class nuclear submarine, was awarded to General Dynamic's Electric Boat Division.