National Nebraska Day is observed worldwide every April 5 to honor Nebraska as the 37th state to join the United States. This day is part of the National State Days project initiated by National Day Calendar in 2017, which celebrates each U.S. state in the order of their admission to the Union. The name "Nebraska" is derived from an archaic Omaha or Otoe term meaning "flat water," referring to the Platte River. Nebraska was inhabited for thousands of years by various Native American tribes before European exploration began in the late 17th century. The state was officially admitted on February 8, 1867, following the Homestead Act of 1862, which encouraged settlement. Notably, Nebraska became the first state to join the Union through a veto override by Congress after President Andrew Johnson vetoed its admission. Celebrations may include educational activities and events that highlight Nebraska's history, culture, and contributions.