The Arengo was formed during High Medieval Times, around the year 1000; it was the very first form of government of the Republic. It was instituted as a result of the need to create a political organ capable of governing and managing the community which had been formed.

The term “Arengo” originally indicated a gathering of all heads of families, who were summoned together by ringing the main bell tower of the church, to decide on and deal with important matters regarding the functioning of the State of San Marino. This body detained all powers, legislative, executive and judicial, which were previously in the hands of one man only, the Abbot feudatory.

The Arengo nominated persons to the highest positions in the State, including the Consuls (latter called Regents). From 1244 the Regents (Captain Regents) took over both executive and judicial activities. The Arengo also began to draw up the statutes (a series of laws to regulate the life of the community).

Around the XV century, with an increasing population, it became more and more difficult to convene all the heads of the families and, above all, to make unanimous decisions. For this reason the Arengo decided to nominate 60 members to carry out all of its ordinary activities (this is the beginning of the Grand and General Council). In this manner an indirect representation of the citizens was obtained.

This system remained in effect until the end of the XVIII century when the political scene became unrelentingly confusing: the Arengo no longer nominated the members of the Council; on the contrary, it was down-rated to a simple ornamental institution. From this moment on, until the Alberonian occupation, a progressive involution took place in the political organization of San Marino. The Council, evading any type of institutional control, was able to domineer the entire political scene, thus protecting the interests of an ever-diminishing number of noble families.

It was only in March 25, 1906, that the Arengo was again convened in the church: the heads of families were 805 out of 1054. Each head of family received a ballot which contained two queries: the first, if the Government of San Marino should be headed by a Main and Sovereign Council; the second, if the number of members of the Council should be proportionate between the city population and the rural population. This was the first attempt to carry out a referendum.

On May 5, 1906, the first electoral law was passed. The law stated that the renewal of the Council was to take place every three years for 1/3 of the assembly and this resulted in an increase of the number of persons who could become members of a voting assembly.

At present the term “Istanza d’Arengo” is used to indicate the presentation on the part of San Marino citizens of petitions regarding questions of public interest, with a six-month cadence (the first Sunday after the 1st of October and the first Sunday after the 1st of April).