From 509-27 BCE, Rome was governed as a Republic that became a model for the United States and other modern governments. During this period, it expanded from a single city to control Italy, Greece, Spain, and much of North Africa. After Julius Caesar was assassinated, Augustus was crowned Emperor, ending the republican period. The country expanded to take over what is today Britain, France, Egypt, Judea, Syria, and Mesopotamia. Emperor Trajan ruled Rome when it was at its largest,