In regards to the Civil War - what side was the union and what side was the confederacy?

The union is the North and the confederacy is the south

explained:

The American Civil War was fought between the United States of America and the Confederate States of America, a collection of eleven southern states that left the Union in 1860 and 1861. The conflict began primarily as a result of the long-standing disagreement over the institution of slavery.

The Union was the North and the Confederacy was the South.