May 21

1865  Sioux and Cheyenne attacked three man party of troopers of the 11th Kansas lead by 2nd. Lt. W. B. Godfrey three miles above Deer Creek Station, Wyoming, while another party of fifty warriors attacked the six man 11th Kansas contingent in a nearby camp.  A party of 200 Indians drove the horse heard off at Deer Creek Station and were given chase by a 30 man contingent of troopers lead by Col Plumb, who were not able to ford the North Platte due to the spring runoff.

1888  Converse County was organized.

1898  Wyoming volunteers for the war in the Philippines arrived in San Francisco and Camp Merritt.

1903 In a speech in Portland Oregon, President Roosevelt declared: "Base is the man who inflicts a wrong, and base is the man who suffers a wrong to be done him."

1911  Porfirio Díaz and Francisco Madero sign the Treaty of Ciudad Juárez.

1918   Tagiro Tanimura of Rock Springs granted a patent for a fountain pen.

1934.  Company No. 844 of the Civilian Conservation Corps arrives at Guernsey State Park to begin work on construction projects.  Ultimately they would go on to build the Officer's Quarters at Camp Guernsey, the new National Guard facility that replaced Pole Mountain as the training range for the Wyoming National Guard.  Camp Guernsey only received one or two annual training cycles prior to World War Two, but has remained the training range since World War Two.  Now much expanded, it is also used by the U.S. Army and the United States Marine Corps for training missions.

After WWII the Guard would install Quonset Huts for the enlisted barracks, but I believe that those were recently replaced.

1942   The Odd Fellows suspended their conventions and put money for the same into war bonds.

1953  Noah W. Riley appointed U.S. Marshall for Wyoming.

1963  Wapiti Ranger Station, the first ranger station constructed in the United States at federal expense, was placed on the National Register of Historic Places.