In June 1907, Mosby wrote a letter to Samuel "Sam" Chapman, in which he expressed his displeasure over people, namely George Christian, downplaying and denying the importance of slavery in its causing the American Civil War. In the letter, Mosby explained his reasons as to why he fought for the Confederacy, despite personally disapproving of slavery. While he admitted that the Confederate states had seceded to protect and defend their institution of slavery, he had felt it was his patriotic duty as a Virginian to fight on behalf of the Confederacy, stating that "I am not ashamed of having fought on the side of slavery—a soldier fights for his country—right or wrong—he is not responsible for the political merits of the course he fights in" and that "The South was my country."