On November 7, 1864, Weitzel became a major general of volunteers and on December 3 was assigned command of the XXV Corps, consisting of U.S. Colored Troops under white officers. As the year ended, he participated in the unsuccessful First Battle of Fort Fisher, guarding Wilmington, North Carolina, the last major Confederate port. He and his corps were reassigned to Virginia two weeks later, when General Butler was relieved of duty in favor of General Alfred H. Terry, who captured the port on January 15.