San Marino has had the same since 1600. The U.S. essentially got a new constitution with the passage of the Reconstruction amendments by 1870.
No, it didn't.
++++++++++++++++++++++++++++++++++++++++++
And it was an elected representative republic for the whole time?
No, it was not an elected representative democracy for its entire history. You are absolutely correct to challenge that assumption.
While its republican institutions survived, the actual method of governance shifted dramatically over the centuries—moving from direct participation to a highly restrictive oligarchy, and even seeing a fascist dictatorship in the 20th century. [
1]
The history of San Marino's governance breaks down into distinct eras:
1. The Early Era: Direct Democracy (301 AD – 1200s)
Originally, San Marino was governed by the
Arengo, an assembly consisting of the heads of every family. This was a form of direct democracy with no single leader. However, as the population grew, this town-hall-style meeting became dysfunctional and plagued by feuds between prominent families. [
1,
2,
3]
2. The Shift to Representative Oligarchy (1600 – 1906)
To fix the chaos of the Arengo, power was gradually shifted to a newly created representative body: the Council of 60 (the Grand and General Council). [
1,
2]
The pivotal transition to a non-elected government came with the
Statutes of 1600: [
1,
2]
- Co-option instead of elections: The Statutes of 1600 established that when a council member died or stepped down, the remaining members would hand-pick their replacement (co-option). [1]
- Rule by elite families: This eliminated popular elections entirely. For three centuries, San Marino operated as an hereditary oligarchy where a small group of patrician and wealthy landowning families completely controlled the State. [1, 2, 3]
3. The Re-Democratic Revolution (1906)
By the early 1900s, popular anger against the ruling elite peaked. On March 25, 1906, the citizens forced the first meeting of the ancestral Arengo (the assembly of householders) in over three centuries. [
1,
2,
3]
- In a massive referendum, 90.6% of voters rejected the oligarchic system of life-long co-option.
- This historic event restored democratic elections to San Marino, establishing the modern parliamentary system used today. [1, 2]
4. The Fascist Interlude (1923 – 1943)
San Marino's democratic continuity was broken again during the 20th century. Following the rise of Benito Mussolini in surrounding Italy, the
Sammarinese Fascist Party (PFS) took total control of the country. They dissolved the democratic council, suspended free elections, and ruled San Marino as a single-party fascist dictatorship for twenty years until they were ousted in 1943. [
1]
Summary
When historians call San Marino the "oldest continuous republic," they mean its
statehood and institutional titles survived without foreign conquest or transformation into a monarchy. The internal system itself has regularly adapted—transitioning from an open commune, to a closed elite oligarchy, briefly to a fascist state, and finally into the modern democratic representative republic it is today.