When was Chamberlain promoted to lieutenant of the 20th Maine?|

Joshua Chamberlain was promoted to lieutenant colonel of the 20th Maine on June 30, 1863, after demonstrating remarkable leadership during the Battle of Gettysburg. His bravery and tactical genius in holding the Union flank at Little Round Top became legendary, solidifying his name in Civil War history. The 20th Maine was a volunteer regiment formed during the Civil War, composed largely of men from Maine. Chamberlain's innovative thinking and adaptability, including the famous "bayonet charge" maneuver he executed on July 2, 1863, not only boosted morale but also played a crucial role in the Union's strategic victory at Gettysburg.