The correct answer is "Great Britain".
The German attack on RMS Lusitania and sinking of the same ship by a submarine caused Americans to join the war. This is just simply put of course, there were many other reasons.
Answer:
President Hayes and the Compromise of 1877
.
Explanation:
The Compromise of 1877 was an informal agreement between southern Democrats and allies of the Republican Rutherford Hayes to settle the result of the 1876 presidential election and marked the end of the Reconstruction era.
After the war peaking in 1946