What term describes the withdrawal from united states by southern in years 1860 and 1861?

The term that describes the withdrawal from the United States by Southern states in the years 1860 and 1861 is secession.

Secession is the act of withdrawing from an organization or political entity, especially a state or country. In the context of the United States, secession refers to the withdrawal of eleven southern states from the Union in the years leading up to the American Civil War.

The secession crisis began in 1860 when Abraham Lincoln was elected president on a platform that opposed the expansion of slavery into new territories. In response, seven Southern states seceded from the Union and formed the Confederate States of America. The remaining four Southern states seceded in 1861 after Confederate forces attacked Fort Sumter in South Carolina.

The American Civil War lasted from 1861 to 1865 and ended with the victory of the Union. The Confederate states were reintegrated into the Union, and slavery was abolished.