The Roman Empire simply became too big. Rome became too extended, too expensive to be sustained by the available resources, and no fundamental technological breakthrough was available to enlarge these resources. In the Roman Empire between 235 and 284 C.E, some twenty-six individuals claimed the title of Roman emperor, only one of whom died of natural causes. The population of the Roman empire declined by 25% in the two centuries following 250 C.E, a demographic disaster that meant diminished production, less revenue for the state, and fewer men available for the defense of the empire’s long frontiers.