American Civil War: <a href="https://en.wikipedia.org/wiki/Battle_of_Mill_Springs" id="mwjw" rel="mw:WikiLink" title="Battle of Mill Springs">Battle of Mill Springs</a>: The <a href="https://en.wikipedia.org/wiki/Confederate_States_of_America" id="mwkA" rel="mw:WikiLink" title="Confederate States of America">Confederacy</a> suffers its first significant defeat in the conflict.