Answer:
One theme that describes at least three major events or turning points of U.S. history before 1877 is the American Revolution. The American Revolution was a political upheaval in the 18th century in which the thirteen colonies broke from British rule and formed an independent nation, the United States of America.
Another event is the Civil War which was fought between 1861 and 1865 and was a turning point in American history. It resulted in the abolition of slavery and the reconstruction of the South.
The Louisiana Purchase is another major event that occurred before 1877. It was a land deal between the United States and France in which the U.S. acquired approximately 827,000 square miles of land west of the Mississippi River for $15 million dollars.
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