Which battle is credited with beginning trench warfare? Battle of Gallipoli
Battle of Ypres
Battle of the Marne
Battle of Tannenberg

The answer is the Battle of the Marne.

Explanation:

This is because a gap ended up between the German and French lines which could cause the French to flank them so the Germans had to push back. The Allies launched a counter-attack so the German had to dig into positions and the Allies did the same.

For nearly a century, the people and politicians of the Northern and Southern states had been clashing over the issues that finally led to war: economic interests, cultural values, the power of the federal government to control the states, and, most importantly, slavery in American society.

Explanation:

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