Already in the monarchical constitution there had been the three elements of political organisation common to the Aryan peoples, the King, the Council of Elders (senatus, connected with senex), and the Assembly of the people.
Of the distribution of functions between the three we know nothing, nor is it likely that the constitution was at all definite. The king was leader in war and chief priest, and exercised some judicial functions; the senate was his council. Presumably the questions which were reserved for the assembly of the whole people varied a good deal with the character of the king; a weak king would ask the people's approval for a proposed course of action where a strong one would do without it.
In republican times two of the elements survive, the senate and the assembly, and indeed the third does not suffer as much change as would appear, for the magistrates are the successors to the royal power. When the change from monarchy to republic was made two magistrates called "consuls" were elected as heads of the state in place of the king, but the royal power was not cut down. It was limited, indeed, by the fact that there were now two heads instead of one and by the fact that the consuls only held office for a year, whereas the kings had held it for life, but, apart from this, the consuls had still the great powers which the king had exercised. In course of time these powers were restricted by statute, but there remained throughout a large residue undefined by strict law, though generally controlled by the conventions of the constitution. The name of this undefined power, at first given to the consuls alone but afterwards to a few other magistrates, is imperium.
The magistracy was originally confined to the patricians, the plebeians being ineligible, and this was one of the points round which the struggle of the orders centred.
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- The republican constitution
+ The struggle between the orders
+ The assemblies of the people
+ Characteristics and procedure of roman assemblies
+ The Senate
+ The consulate
+ The praetorship
+ The aedileship
+ The quaestorship
+ The censorship
+ The tribunate
+ The dictatorship
+ The minor magistrates
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Source:
Historical introduction to the study of Roman law, H. F. Jolowicz, page 7.