Following his graduation, Pitkin would practice law while serving as a school principal in New Orleans between the years of 1861 to 1863. During the Civil War, he would find himself briefly serving as a private in Louisiana's Crescent Regiment, beginning in February 18, 1863. However, after the fall of New Orleans, he publicly declared himself a Republican and Unionist, earning him a position in the Reconstruction. He would participate in the Southern Loyalist convention, held in Philadelphia in 1866, and would serve as a Republican campaign speaker.