Tetrarchys
Tetrarchy refers to a system of government where power is divided among four rulers. The most famous historical example is the Tetrarchy established by Roman Emperor Diocletian in 293 AD. Diocletian divided the Roman Empire into Eastern and Western halves, each ruled by an Augustus (senior emperor) and a Caesar (junior emperor). This system aimed to provide better administration and defense for the vast empire.
Under Diocletian's Tetrarchy, the two Augusti were Diocletian himself and Maximian. They appointed two Caesars, Galerius
While initially successful in stabilizing the Roman Empire and repelling external threats, the Tetrarchy ultimately proved