The earliest systematic description of the Roman state structure belongs to the Greek historian Polybius. He faced the beginning of Roman rule when the West and the Hellenistic East were combined into a single whole. The great historian wrote forty novels about ancient Rome. In Book VI the Roman system of government is explained thoroughly. The main concern of Polybius was to find out the reason for the gradual growth of Rome’s power and explain the fact of their world domination. In Book VI, Polybius discloses the specialties of Roman government structure that led to political success and sustainability. Polybius considered Rome’s growth to be not a simple accident, but a natural and logical process, a necessary consequence of historical development.
Polybius’s account of the Roman constitution combines two aspects: theoretical and practical. The historian begins with a general discussion of how constitutions develop and change. He considers the basis for the development of constitutions to be the biological law of birth, growth, and decline. Each separate form of government is born, flourishes, and fades away in accordance with a biological principle. The biological law corresponds to the scheme of six traditional state structures, three of which (royal power, aristocracy, democracy) are proper but tend to degenerate into tyranny, oligarchy, and ochlocracy (crowd power).
Each constitution goes through all three stages in its development and returns to the starting point of development – the rule of one person. Polybius called such consequences “the cycle of the state community” and “the order of nature”. The passage of all stages of constitutional development forms the constitutional cycle (anakyklosis). The evolution of the forms of the state is, therefore, the external form of historical movement. The desire to find a way out of the fatal process of degeneration of simple state forms led Polybius to mixed constitution and its relationship with the constitutional cycle.
The unification of three powers in a single political organism does not mean for Polybius their simple mechanical mixing. The ideal, which the Roman state was, is achieved by balancing the three organs of power and their mutual restraint. The contents of Roman history allowed Polybius to give a finished form to the theory of mixed state structure that he knew from the writings of his predecessors. The Roman state was a republic following certain laws, customs, and norms. The major branches were ruling the state: the Senate, the magistrates (representatives from people), and the Assemblies that were the supreme organ of justice and power. The executive branch was mostly held by magistrates that were elected in one year and were not receiving any salary. Consequently, magistrates could not be from low-income society groups. Royal power was in the arms of magistrates and councils, the aristocracy was held by Senate, and democratic – in the Assembly. All three branches were interconnected, and none of them had unlimited power and decision-making autonomy.
Thus, the Roman republic in book VI of Polybius represents a successful implementation of a mixed constitution. The author stated that a mixed constitution created balance and sustainability to the constitutional cycle that brought stability to the government. Polybius also believed external political achievements occurred due to such a smart government structure. The Roman republic remains one of the most attractive political structures in world history and investigating it might lead to some positive changes in the current system.
Reference
Polybius, Ian Scott-Kilvert, and F. W. Walbank. 1979. The Rise of the Roman Empire, Harmondsworth: Penguin.