The Fourth Sacred War was a war of Greek city states fought from 339 to 338 B.C. Demosthenes of Athens a famous orator was successful in getting people of Athens and Thebes to unite together against the growing power of Philip of Macedon and the Amphictyonic Council. They declared war, but lost the Battle of Chaeronea leaving Philip as the unquestioned master of Greece.
Sources
Encyclopedia of Military History, Dupuy & Dupuy, 1979