1808 John Jacob Astor incorporates the American Fur Company.
1830 Mexico halts American immigration into Texas. Attribution: On This Day.
1860 First west bound Pony Express arrives at Fort Laramie.
1862 John Wesley Powell, after whom Powell is named and who would become a noted post Civil War explorer, lost his right arm in the Battle of Shiloh.
1866 The Grand Army of the Republic, the veterans organization of Union soldiers, founded. There are at least two GAR memorials in Wyoming, with one being located in Casper and another being located in Big Horn.
1880 Cowboy hopeful Charles Russell arrived in Utica Montana.
1887 Cheyenne & Burlington Railroad Company filed articles of incorporation as a foreign corporation. The railroad is a predecessor of the Burlington Northern.. Attribution: On This Day.
1892 Special train carrying the "Invaders", hired gunmen and representatives of large cattle interests, arrives in Casper and discharges its passengers under darkness, at about 4:00 AM. The chartered train arrived with its window shades drawn, but the secrecy associated with it only encouraged rumors as to its cargo. They traveled a few miles north of Casper and assembled at Casper Creek at about 9:00 AM. Delays soon set in, with horses breaking fee and requiring hours to be rounded up. Some horses were never found and the men whose mounts those were rode in wagons. As it had snowed, traveling by wagon proved slow. The party made 20 miles that day.
For perspective, a typical long day for an Oregon Trail party was about 30 miles in a day, although many were shorter. The cavalry of the period typically made 30 miles a day, although they could go further.
For the first time since the Columbus Raid, the Punitive Expedition didn't make the front page for the Casper Daily Press.
1917 Congress approved a declaration of war against Germany at 3:08 a.m.
The Cheyenne State Leader for April 6, 1917: Duels of Nations and Duels of Indiviuals
The news was all about duels.
The United States had entered the duel with Germany.
Villa was moving in his duel with Carranza.
And a farmer died in a duel with a cowboy near Sheridan.
And the Wyoming National Guard's Second Battalion had been called fully back into service.
1920 Work began on the Standard Oil Refinery in Laramie. Attribution: Wyoming State Historical Society.
1960. Esther Morris statue dedicated in Statuary Hall, U.S. Capitol. Attribution: Wyoming State Historical Society.
1999 A 4.6 magnitude earthquake occurred about 35 from Rawlins, WY.