In 371BCE, Thebes dealt Sparta, the reigning hegemon of Greece, a blow it would never recover from. An innovative mix of hoplite tactics allowed Theban General Epaminondas to win a landmark strategic victory that put Thebes on the map... for about 30 years before they screwed it all up.

Sources:

Hanson, Victor Davis, "The Leuktra Mirage"

Ray Jr., Frank Eugene, "Greek and Macedonian Land Battles of the 4th Century BC," McFarland, 2012.

Xenophon, "Hellenica"

Battle (Normal)-Boxcat Games

Licensed under Creative Commons: By Attribution 3.0 license

https://creativecommons.org/licenses/by/3.0/

Mission-Boxcat Games