The Centuriate Assembly was one of the governing bodies of the Roman Republic. The Centuriate Assembly is so named because it divided the Roman population into one hundred groups, each with their own representative in the assembly. The Centuriate Assembly was the most powerful assembly for most of the history of the Roman Republic. The Centuriate Assembly was responsible for declaring war and was the only governing body which could elect magistrates like praetors, consuls, and quaestors.

In the very early years of the Roman Republic, power and wealth was concentrated in the hands of the landowning aristocratic class, called the patricians. The plebeians, the common people of Rome, had little political power and were subject to forced enslavement and unequal protection before the law. The patricians and plebeians competed for political power throughout the history of the Roman Republic. One notable incident occurred with the Secession of the Plebs in 494 BCE (which began the two centuries long Struggle of Orders). The Plebeians basically abdicated responsibility for the maintenance of the city and carried out something like a “general strike.” This, most significantly, included the threat to withhold military service and force the patricians to fight to defend themselves.

Consuls were the highest elected officials in the Roman Republic. Two consuls were appointed at one time to serve concurrently for terms of one year. They had numerous responsibilities, including leading the armies of the Roman Republic in times of war. They were more likely to be patricians (noblemen) than plebeians. They did not, however, generally have dictatorial levels of power. Rome sometimes did require temporary dictators, in times of war or chaos, but these dictators were distinct from consuls.

The Secession of the Plebeians took place in 494 BCE. It is best described as a general strike, organized by the common people of Rome, to gain political power. There were other plebeian secessions throughout the history of the Roman Republic, such as the one carried out in 449 BCE, which was done to ensure the patricians would enact the Law of Twelve Tables. The plebeians would “secede” from the Republic in order to pressure the patricians into accepting reforms that would make the lives of plebeians better.

The Tribune of the Plebs was created in the early years of the Roman Republic, around 495 BCE. It was the result of class tensions between the ruling patricians and the relatively powerless plebeians. These class tensions would continue for at least another two centuries (and essentially throughout the entire history of the Roman Republic), but the Tribune of the Plebs was in existence for almost all of these struggles. The Tribune of the Plebs was capable of taking legislative action, but initially only the plebeians were obligated to follow these “plebiscites.”

A plebiscite was a law enacted by the Council of Plebeians in the Roman Republic. Generally, the law applied only to common people — the plebeians — and was not applicable to the aristocratic class, the patricians.

Tiberius and Gaius Gracchus were brothers who served as plebeian tribunes in the second century BCE. They were both populares, which means they achieved political power through the support of the common people and the assemblies. They are both remembered for their attempts to improve the lives of poor plebeians in the Roman Republic. Tiberius tried to accomplish this by taking land away from the richest members of society and redistributing it to the poor. Gaius went even further than his brother in his attempted reforms, but his actions eventually led to the outbreak of the Social War and civil war in the Roman Republic.

Plebeian tribunes were the primary representation of the common people of Rome in the government of the Roman Republic. Plebeian tribunes were appointed to represent the interests of the plebeian class and wielded a considerable amount of political power, particularly towards the end of the history of the Roman Republic. The most significant, and first, political power of the plebeian tribunes was the ability to veto decisions made by consuls and magistrates. This was a significant check that the plebeians had on the power of the patricians.

In the Roman Republic there were many different types of assemblies, all of which had different degrees of power. Some assemblies were comprised of all Roman citizens and were responsible for electing magistrates, enacting laws, and conducting legal trials. Other assemblies included councils, like the Council of Plebeians, which passed laws that only affected the plebeians (common people of Rome). The authority of various assemblies waxed and waned throughout the history of the Roman Republic, as different governing institutions squabbled with one another for political power.

The Romans overthrew rule by the Etruscans during the Roman-Estruscan Wars. This victory was monumental in the formulation of the Roman Republic. The Etruscans supported the deposed king Lucius Tarquinus Superbus with a military showing, but were thoroughly defeated by Roman Republic forces at the Battle of Silva Arsia. The other answers are incorrect because these groups posed threats at later times in Roman history.