American Civil War

The American Civil War (1861–1865), also known as the War Between the States and several other names, was a civil war in the United States of America. Eleven Southern slave states declared their secession from the U.S. and formed the Confederate States of America (the Confederacy). Led by Jefferson Davis, they fought against the U.S. federal government (the Union), which was supported by all the free states and the five border slave states in the north.

There is only one known demigod involved in this war, although numerous children of Athena and Ares probably fought. Harriet Tubman was a child of Hermes.

The Sea of Monsters
In the book The Sea of Monsters, Clarisse help Percy, Tyson, and Annabeth defeat the Hydra with a Confederate Ironclad warship. The book mentioned that in every war, the losing side dies within Ares's hand. Then Ares controls them.

The Lost Hero
The Roman and Greek Demigods had a giant battle around the time of the Civil War. This caused the gods to separate them and weave the Mist as tightly as possible so the two sides never remembered each other.