After the war he studied law, passed the bar and set up practice in Mineral Point, Wisconsin.

On November 4, Cobb's men fought off an attack by John Bell Hood's Confederates led by Major General Nathan Bedford Forrest in the Battle of Johnsonville.

For the rest of the war, the regiment was positioned in various parts of Tennessee to guard railroads and supply routes, and Cobb briefly commanded a brigade under Major General Robert H. Milroy.

On January 13, 1866, President Andrew Johnson nominated Cobb for appointment to the grade of brevet brigadier general of volunteers to rank from March 13, 1865, for his distinguished services at the Battles of Williamsburg, Golding's Farm, Virginia, during the Seven Days Battles and Antietam,[2] and the United States Senate confirmed the appointment on March 12, 1866.

[1][5] After the war, Cobb became a member of the Military Order of the Loyal Legion of the United States.