Final answer:
The issue of whether slavery would be permitted in new territories in the United States was decided through events and compromises such as the Missouri Compromise and the Kansas-Nebraska Act. This issue played a significant role in causing the American Civil War.
Step-by-step explanation:
In the United States, the issue of whether slavery would be permitted in new territories was decided through a series of events and compromises. One of the key events was the Missouri Compromise of 1820, which allowed Missouri to enter the Union as a slave state and Maine as a free state, while also establishing a line at latitude 36°30' where future states would decide on the issue of slavery. Another significant event was the Kansas-Nebraska Act of 1854, which introduced the concept of popular sovereignty, granting residents of these territories the right to decide on the issue through voting. Ultimately, the question of whether slavery would be permitted in new territory was a central cause of the American Civil War.
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