Here is the full list of all 50 The History Channel: Civil War - there are A Nation Divided achievements worth 1,000 gamerscore.
To earn this award you must kill 20 of your enemies.
To earn this award you must kill 50 of your enemies.
To earn this award you must kill 100 of your enemies.
To earn this award you must kill 250 of your enemies.
To earn this award you must kill 500 of your enemies.
To earn this award you must kill 750 of your enemies.
To earn this award you must kill 100 of your enemies with your pistol.
To earn this award you must kill 75 of your enemies with your knife.
To earn this award you must kill 50 of your enemies in close combat.
Complete the game on the Easy (or higher) difficulty setting.
Complete the game on the Normal (or higher) difficulty setting.
Complete the game on the Hard difficulty setting.
To earn this award you must find all secret photographs in the game.
To earn this award you must find all secret documents in the game.
Complete the Fredericksburg mission.
Complete the Fredericksburg mission with an accuracy above 75%.
Complete the Fredericksburg mission with an accuracy above 95%.
Complete the Gettysburg mission.
Complete the Gettysburg mission with an accuracy above 75%.
Complete the Chattanooga mission.
Complete the Chattanooga mission with an accuracy above 75%.
Complete the Fort Fisher mission.
Complete the Fort Fisher mission with an accuracy above 75%.
Complete the Fort Fisher mission with an accuracy above 95%.
Complete the Selma mission.
Complete the Selma mission with an accuracy above 75%.
Complete the Selma mission with an accuracy above 95%.
Complete the Petersburg mission.
Complete the Petersburg mission with an accuracy above 75%.
Complete the Petersburg mission with an accuracy above 95%.
Complete the Bull Run mission.
Complete the Bull Run mission with an accuracy above 75%.
Complete the Bull Run mission with an accuracy above 95%.
Complete the Shiloh mission.
Complete the Shiloh mission with an accuracy above 75%.
Complete the Shiloh mission with an accuracy above 95%.
Complete the Antietam mission.
Complete the Antietam mission with an accuracy above 75%.
Complete the Antietam mission with an accuracy above 95%.
Complete the Chancellorsville mission.
Complete the Chancellorsville mission with an accuracy above 75%.
Complete the Chancellorsville mission with an accuracy above 95%.
Complete the Chickamauga mission.
Complete the Chickamauga mission with an accuracy above 75%.
Complete the Chickamauga mission with an accuracy above 95%.
Complete the Cold Harbor mission.
Complete the Cold Harbor mission with an accuracy above 75%.
Complete the Cold Harbor mission with an accuracy above 95%.