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 and Constantius Chlorus, who were their designated successors. The empire was further divided into four administrative regions, each under the primary responsibility of one tetrarch. This arrangement sought to ensure stability by having multiple rulers with defined spheres of influence and a clear line of succession.

While initially successful in stabilizing the Roman Empire and repelling external threats, the Tetrarchy ultimately proved unstable. Internal rivalries and power struggles emerged after Diocletian and Maximian abdicated in 305 AD, leading to civil wars and the eventual collapse of the system. Despite its eventual failure, the concept of dividing power among multiple rulers has appeared in various forms throughout history and political thought.