Tetrarch

Tetrarch, Tetrarchs, or Tetrarchy may refer to:


 * Tetrarch (Greek rank) in ancient Greek armies
 * Tetrarch (Macedonian rank)
 * Tetrarch tank, a British light tank of World War II
 * Tetrarches, a rank in the Byzantine army
 * Tetrarchy, a subdivision of the Royal Phalanx in 19th-century Greece