San Marino was originally led by the Arengo, initially formed with the heads of
each family. In the 13th century, power was given to the Great and General Council.
In 1243, the first two Captains Regent were nominated by the Council. This method
of nomination is still in use today. Every 6 months, the Council elects two Captains
Regent to be the heads of state. They are chosen every April 1 and October 1.
The practice of multiple heads of state, as well as the frequent re-election of
the heads of state, are derived directly from the customs of the Roman Republic.
The Council is equivalent to the Roman Senate; the Captains Regent, to the consuls
of ancient Rome.