Answer:
The first American troops landed at Salerno on 9 September 1943, by U.S. 5th Army, however, German troops in Italy were prepared and after the Allied troops at Salerno had consolidated their beachhead, The Germans launched fierce counterattacks.
Explanation:
This is most likely specifically asking for World War I.
The first thing is rather not a gain, but a trust. Most of Europe, Asia, as well as the Middle East and Africa, were split into two camps. These camps were alliances, known as the Central Alliance (the German & Austrio-Hungary camp), and the Allies (The British & French camp).
The war was triggered by the assassination of Archduke Franz Ferdinand and his wife Sophie by a Serbian Nationalist who wanted to see a free Serbia. While Serbia was open to paying for reparation, Austrio-Hungary threw away the table in hopes of conquering and claiming Serbia for their own. The failure for the gears of war to stop before then was what caused the countries to go at war. Each country was bound by their alliance contract to help their members at need, and so it set off a chain reaction that ensued into a global war.
They had nothing to gain, but to keep their own honor, the survivability of their state, and the trust of their allies.
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The Babylonian economy was largely based on agricultural surplus (due to irrigation systems) and trade. They traded both crops and goods like gold, silver, etc.
