On this date, the 4th Wisconsin Cavalry (then an infantry unit) embarked to join the "Army of the Gulf." It arrived below New Orleans on March 12, 1862, and landed in New Orleans on May 1. The 4th was at once assigned to active service and joined an expedition up the Mississippi River against Vicksburg in May. By June they occupied Baton Rouge, Louisiana. The troops there were employed in several successful expeditions during that winter, and remained in the area through most of the war. In June of 1862, its commander was punished for refusing to return escaping slaves to their masters ( on this event is at Turning Points in Wisconsin History). In 1863 the unit was equipped as a Cavalry Regiment; it returned to Wisconsin in 1866. Read more about it in Charles Estabrook’s guide to .