and military obligations of all Roman citizens. As a whole, the so-called Servian reforms probably represent a long-drawn, complex and piecemeal process of populist policy and reform, extending from Servius' predecessors, Ancus Marcius and Tarquinius Priscus, to his successor Tarquinius Superbus, and into the Middle and Late Republic. Rome's military and territorial expansion and consequent changes in its population would have made franchise regulation and reform an ongoing necessity, and their wholesale attribution to Servius "cannot be taken at face value". Curiate reform and census Until the Servian reforms, the passing of laws and judgment was the prerogative of the comitia curiata (curiate assembly), made up from thirty curiae; Roman sources describe ten curiae for each of three aristocratic tribes or clans, each supposedly based on one of Rome's central hills, and claiming patrician status by virtue of their descent from Rome's founding families. These tribes comprised approximately 200 gentes (clans), each of which contributed one senator ("elder") to the Senate. The senate advised the king, devised laws in his name, and was held to represent the entire populus Romanus (Roman people); but it could only debate and discuss. Its decisions had no force unless approved by the comitia curiata. By the time of Servius, if not long before, the tribes of the comitia were a minority of the population, ruling a multitude who had no effective voice in their own government. Rome's far more populous citizen-commoners could participate in this assembly in limited fashion, and perhaps offer their opinions on decisions but only the comitia curiata could vote. A minority thus exercised power and control over the majority. Roman tradition held that Servius formed a comitia centuriata of commoners to displace the comitia curiata as Rome's central legislative body. This required his development of the first Roman census, making Servius the first Roman censor. For the purposes of the census, citizens assembled by tribe in the Campus Martius to register their social rank, household, property and income. This established an individual's tax obligations, his ability to muster arms for military service when required to do so, and his assignment to a particular voting bloc. The institution of the census and the comitia centuriata are speculated as Servius' attempt to erode the civil and military power of the Roman aristocracy, and seek the direct support of his newly enfranchised citizenry in civil matters; if necessary, under arms. The comitia curiata