Nathaniel Lyon was the first Union

Union Army

The Union Army was the land force that fought for the Union during the American Civil War. It was also known as the Federal Army, the U.S. Army, the Northern Army and the National Army...

 general to be killed in the American Civil War

American Civil War

The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...

 and is noted for his actions in the state of Missouri

Missouri

Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It...

 at the beginning of the conflict.

Lyon is a controversial figure in American history. Some credit his quick action and hard line Unionism for stopping the Missouri secession

Secession

Secession is the act of withdrawing from an organization, union, or especially a political entity. Threats of secession also can be a strategy for achieving more limited goals.-Secession theory:...

 movement. Others question his influence peddling and his role in events such as the Camp Jackson Affair, which inflamed many Missourians on the secession issue (See Missouri secession

Missouri secession

During the American Civil War, the secession of Missouri was controversial because of the disputed status of the state of Missouri . During the war, Missouri was claimed by both the Union and the Confederacy, had two competing state governments, and sent representatives to both the United States...

.)
Lyon was born on a farm in Ashford, Connecticut

Ashford, Connecticut

President George Washington, returning from his tour of the country in the fall of 1789, was chagrined to be involuntarily abandoned in the village on a Sunday...

, son of Amasa and Kezia Knowlton Lyon.