The history of Monaco

Monaco is a city-state of about two square kilometres on the Mediterranean coast, wedged between the French Alps and the sea. Its history begins with a rocky headland and a sheltered harbour that drew Ligurian settlers, Greek and Phoenician sailors and Roman travellers. From the thirteenth century the Rock was a Genoese fortress, and since 1297 it has been ruled, with interruptions, by the Grimaldi family, one of the oldest reigning dynasties in Europe. The principality survived by placing itself under the protection of stronger neighbours, first Spain, then France and Sardinia, and in the nineteenth century it remade itself through the casino of Monte Carlo into a resort and financial centre.

Caves on the slopes above the harbour, among them the Observatoire cave beneath today's Exotic Garden, preserve traces of Palaeolithic hunters. The first settled inhabitants known to ancient writers were the Ligurians, a people who held much of the coast between the Rhône and the Arno. Sailors from Phoenicia are said to have used the harbour, and in the sixth century BCE Greeks from Massalia, today's Marseille, founded a small colony there. They called it Monoikos, a name connected with Heracles, who was worshipped on the headland, and the harbour became known as the Port of Hercules.

Rome brought the coast under control in the first century BCE, and the area became part of the province of the Maritime Alps. On the heights at La Turbie, just above Monaco, Augustus raised a great trophy celebrating his conquest of the Alpine tribes. Roman writers, including Virgil and Pliny the Elder, mention the port as a stopping place for ships along the coast.

After the fall of the Western Roman Empire the coast passed through the hands of Ostrogoths, Byzantines, Lombards and Franks, and in the eighth to tenth centuries it suffered from Saracen raids. In 1191 the emperor Henry VI of the Holy Roman Empire granted the Rock and harbour to the Republic of Genoa, on condition that it be fortified against pirates. In June 1215 Genoese Ghibellines under Fulco del Cassello began a fortress of four towers joined by a curtain wall, which became the core of the Prince's Palace.

Genoa was torn by feuds between the Ghibelline faction and the Guelphs, among whom the Grimaldi family were prominent. On 8 January 1297 François Grimaldi, nicknamed Malizia, entered the fortress disguised as a Franciscan friar and took it with his men. The story is partly legend, and the family's hold was not secure: the fortress was lost and retaken several times over the next decades. Charles I Grimaldi is regarded as the first lord of Monaco, from 1341, and the family added Menton in 1346 and Roquebrune in 1355, enlarging their territory many times over. In 1419 the Grimaldis bought out the claims of the Crown of Aragon and became Monaco's undisputed rulers. Lambert Grimaldi, in the later fifteenth century, strengthened the defences and kept a garrison of some 400 men, and Monaco withstood Genoese sieges in 1505 and 1507.

The lords of Monaco survived by choosing powerful protectors. After Lucien Grimaldi was murdered in 1523, his successor Augustin turned to Spain, and the Treaty of Burgos of 1524 placed Monaco under the protection of the Spanish Empire, with a Spanish garrison on the Rock. Under Honoré I the old fortress was rebuilt as a Renaissance palace with frescoed galleries. Honoré II began calling himself prince in 1612, a title Spain recognised in 1633, but he grew tired of Spanish control. By the Treaty of Péronne of 1641 he switched to the protection of the Kingdom of France, expelled the Spanish garrison, and received French titles and estates in return. For the next century and a half the princes spent much of their time at the French court.

The male Grimaldi line ended in 1731. The heiress Louise-Hippolyte had married Jacques de Goyon de Matignon, a Norman nobleman, who took the Grimaldi name, and their descendants have reigned ever since.

The French Revolution swept the princes away. In 1793 France annexed Monaco, the palace was looted and turned into a military hospital and poorhouse, and members of the family were imprisoned. The Grimaldis regained their principality in May 1814, and the Congress of Vienna in 1815 placed it under the protection of the Kingdom of Sardinia.

The restored princes taxed their subjects heavily, and in 1848 Menton and Roquebrune, which made up most of the principality's land and wealth, rose in revolt and declared themselves free towns. When Sardinia ceded Nice to France in 1860 as part of the bargain behind the unification of Italy, Monaco was left surrounded by French territory. Prince Charles III accepted reality: in the Franco-Monegasque Treaty of 1861 he gave up his claim to Menton and Roquebrune for about four million francs, and France recognised Monaco's sovereignty.

Reduced to a tiny territory, Charles III looked for new income. In 1856 he granted a concession for sea baths and a German-style gambling house, and after early failures the casino settled on the Spélugues plateau, which was named Monte Carlo, "Mount Charles", in 1866. The railway along the coast reached Monaco in 1868 and brought wealthy visitors in large numbers. Casino revenues were so large that in 1869 the principality stopped collecting income tax from its residents.

Albert I, who reigned from 1889 to 1922, was a naval officer and pioneering oceanographer who led scientific cruises from the Azores to Svalbard and opened the Oceanographic Museum on the Rock in 1910. Protests that year, known as the Monegasque Revolution, pushed him to grant a constitution in January 1911, ending absolute princely rule. A treaty of 1918 tied Monaco more closely to France, providing that its policy would be aligned with French interests. Under Louis II, Monaco began hosting its motor-racing Grand Prix in 1929.

During the Second World War Louis II tried to keep Monaco neutral. Italian troops occupied it in November 1942, and after Italy's surrender German forces took over in September 1943 and began deporting Jews. In August 1944 the Germans executed three leaders of the resistance, and Allied forces liberated Monaco on 3 September 1944. In 2015 Albert II formally apologised for the principality's part in handing over some 90 Jews and resistance members, victims of the Holocaust.

Rainier III succeeded his grandfather in 1949 and reigned for 56 years. His marriage to the American film star Grace Kelly in 1956 brought Monaco worldwide attention. Rainier worked to broaden the economy beyond gambling, towards tourism, banking, property and light industry, and land reclaimed from the sea, notably the Fontvieille district, enlarged the territory. The constitution of 1962 abolished the death penalty, gave women the vote and created a Supreme Court. The same year Monaco's status as a tax haven for French citizens provoked a crisis with France: President Charles de Gaulle responded with customs controls that amounted to a blockade of the principality, and the dispute ended in 1963 with an agreement that most French nationals living in Monaco would pay French tax.

Monaco joined the United Nations as a full member in 1993 and the Council of Europe in 2004. A treaty with France in 2002 replaced the old rule that Monaco would become a French protectorate if the dynasty died out, confirming that the principality would remain independent, while France remains responsible for its defence. Rainier III handed his duties to his son Albert on 31 March 2005 and died six days later, and Albert II was formally enthroned that July.

Under Albert II, Monaco has continued to grow outward into the sea, with the new Le Portier district, also known as Mareterra, opening in 2024. That June the Financial Action Task Force placed Monaco on its list of jurisdictions under increased monitoring for money-laundering risks. Christophe Mirmand became minister of state, the head of government appointed by the prince, in July 2025, and in March 2026 Pope Leo XIV visited the principality, whose state religion remains Roman Catholicism.