tunately, Romulus and Remus argued about whom would rule the city, which led to Romulus killing Remus. Romulus then named the city "Rome", after himself. (Haywood, p. 195)
Rome eventually was at war with its neighbor, the Sabines. It started when Rome had a low number of marriageable women in its city. Romulus decided to invite the Sabines to a feast. At the feast, the Roman men seized the Sabine women. It was at that time a war erupted between the Rome and Sabines. The war was eventually ended through the intervention of the Sabine women. An agreement was eventually made between Romulus and the Sabine people. The Sabines and Rome would combine to become one tribe. It placed Rome under the joint rule of Romulus and Titus Tatius, the Sabine leader. (Haywood, p. 195) This was how Rome was started mythically.
Of course, Rome has always been known for its government, the republic. This was not how Rome was first ruled. As stated earlier, Rome started out being ruled jointly within the myth, but the successor of the joint rule was the Sabine king, Numa Pompilius, who was indeed a proven historical figure. Although Rome enjoyed many years of peace under the rule of Numa Pompilius, his successors were very much war-like and proceeded to lead Rome into an expansive campaign. It wasn't until Servius Tullius seized the throne after a palace riot killed his father in law, Tarquin I. (Haywood, p. 198)
Servius brought about many changes while he was in power. He changed the basis of citizenship within Rome from birth to residence. This made Rome more welcoming to immigrants. He also formed a new assembly, the comitia centuriata. This created voting units called centuries and divided the people into different classes by how much they owned. Servius also laid claim to the surrounding countryside and increased the Roman population. This led to the greater expansion of Rome. (Haywood, p. 198)
Servius Tullius eventually died...