June 4

1812 By act of Congress approved June 4, 1812, the Territory of Louisiana became the Territory of Missouri. Most of Wyoming then existed as the Territory of Missouri.

1879 Big Horn Post Office was established on June 4, 1879 in Pease County. Pease County was renamed Johnson County later in 1879 and Sheridan County, in which Big Horn still exists, was established in 1888.

1931 On this day in 1931, Amelia Earhart flew across Wyoming as part of a cross-country flight in her Beech-Nut Autogiro. She left Cheyenne airport around 9 a.m. and made fuel stops in Laramie, Parco, Rock Springs, and LeRoy during the day. Read more about Earhart's shining adventures in Wyoming and the "Weird Windmill Ship" she flew here.