A system of government ran by ellected officials. Not a rare system of government at all. Republic by definition does not imply a concern for human rights or an inclusive democratic system. It just means that a governing body (aristocracy, military, general population, etc) ellected a head of state. Republics are by no means rare and are not necsessarily short lived. In fact, of the almost 200 currently existing soverign states in the world currently, roughly half of them are republics. And the republic of San Marino has had a life span of roughly 1700 years.
The United States of America, the People's Republic of China, etc.