Excerpts from Books and Wikipedia
"The Second Battle of Mantinea was fought on July 4, 362 BC between the Thebans, led by Epaminondas and supported by the Arcadians and the Boeotian league against the Spartans, led by King Agesilaus II and supported by the Eleans, Athenians, and Mantineans. The battle was to determine which of the two alliances would have hegemony over Greece. However, the death of Epaminondas and his intended successors coupled with the impact on the Spartans of yet another defeat weakened both alliances, and paved the way for Macedonian conquest led by Philip II of Macedon." [Wikipedia]