The Twentieth Maine A painting depicts Union Army Col. Joshua L. Chamberlain ordering the men of the 20th Maine Infantry to run down Little Round Top and push back the Confederate soldiers during the Battle of Gettysburg, July 2, 1863. SHARE IMAGE: Download Image: Full Size (0.36 MB) Photo By: National Guard Bureau/H. Charles McBarron VIRIN: 180320-Z-KE703-1005C.JPG Photo Gallery