History has demonstrated that amphibious assaults are among the most complex and challenging of all joint operations. The myriad of factors that evolved independently throughout the war did not become fully integrated until the winter of 1864-65. This thesis explores the maturation of joint amphibious operations during the U.S. Civil War, specifically through the assaults on Fort Fisher. This analysis will use modern joint doctrine as the framework to compare and contrast the two assaults. It will elaborate on how seaborne assaults differ from riverine assaults. Utilizing Fort Fisher as the focus develops an understanding of the interrelationship of these various factors and the challenges posed in their synchronization to achieve success. This study concludes that the operations reflected jointness, but also marked the emergence of modern amphibious assault concepts.