The Story of the World: History for the Classical Child, Volume 1: Ancient Times: From the Earliest Nomads to the Last Roman Emperor

by Susan Wise Bauer

So instead of remaining on friendly terms, Sparta and Athens began to fight with each other again. The war between Sparta and Athens began in 431 BC/BCE. It had a very long name—the Peloponnesian War. And the Peloponnesian War went on for a long time, over 25 years.