Detailed Instructions: Generate a correct and concise answer for the question based on the words in the context.
Problem:Context : William J. Archinal (June 3, 1840 -- May 10, 1919) was an American Civil War Union Army soldier who received the Medal of Honor for his actions at the Battle of Vicksburg.
Question : Which war was William J. Archinal a part of?
Solution:
American Civil War