Republic of Genoa in the context of "Autonomous Republic of Crimea"

A city-state is an independent sovereign city which serves as the center of political, economic, and cultural life over its contiguous territory, as opposed to a regular state or country comprising a capital city and other cities and/or a countryside. City-states have existed in many parts of the world throughout history, including cities such as Rome, Carthage, Athens and Sparta and the Italian city-states during the Middle Ages and Renaissance, such as Florence, Venice, Genoa and Milan.

With the rise of nation states worldwide, there remains some disagreement on the number of modern city-states that still exist; Singapore, Monaco and Vatican City are the candidates most commonly discussed. Out of these, Singapore is the largest and most populous city-state in the world, with full sovereignty, international borders, its own currency, a robust military, and substantial international influence in its own right. The Economist refers to it as the "world's only fully functioning city-state".

Crimea (/kraɪˈmiːə/ kry-MEE-ə) is a peninsula in Eastern Europe, on the northern coast of the Black Sea, almost entirely surrounded by the Black Sea and the smaller Sea of Azov. The Isthmus of Perekop connects the peninsula to Kherson Oblast in mainland Ukraine. To the east, the Crimean Bridge, constructed in 2018, spans the Strait of Kerch, linking the peninsula with Krasnodar Krai in Russia. The Arabat Spit, located to the northeast, is a narrow strip of land that separates the Syvash lagoons from the Sea of Azov. Across the Black Sea to the west lies Romania and to the south is Turkey. The population is 2.4 million, and the largest city is Sevastopol. The region, internationally recognised as part of Ukraine, has been under Russian occupation since 2014.

Called the Tauric Peninsula until the early modern period, Crimea has historically been at the boundary between the classical world and the steppe. Greeks colonised its southern fringe and were absorbed by the Roman and Byzantine Empires and successor states while remaining culturally Greek. Some cities became trading colonies of Genoa, until conquered by the Ottoman Empire. Throughout this time the interior was occupied by a changing cast of steppe nomads, coming under the control of the Golden Horde in the 13th century from which the Crimean Khanate emerged as a successor state. In the 15th century, the Khanate became a dependency of the Ottoman Empire. Lands controlled by Russia and Poland-Lithuania were often the target of slave raids during this period. In 1783, after the Russo-Turkish War (1768–1774), the Russian Empire annexed Crimea. Crimea's strategic position led to the 1854 Crimean War and many short lived regimes following the 1917 Russian Revolution. When the Bolsheviks secured Crimea, it became an autonomous soviet republic within the Russian Soviet Federative Socialist Republic. It was occupied by Germany during World War II. When the Soviets retook it in 1944, Crimean Tatars were ethnically cleansed and deported under the orders of Joseph Stalin, in what has been described as a cultural genocide. Crimea was downgraded to an oblast in 1945. In 1954, the USSR transferred the oblast to the Ukrainian Soviet Socialist Republic on the 300th anniversary of the Pereyaslav Treaty in 1654.

The Sultanate of Rum, or Seljuk Empire of Rum, was a culturally Turco-Persian Sunni Muslim state, established over conquered Byzantine territories and peoples (Rum) of Anatolia by the Seljuk Turks following their entry into Anatolia after the Battle of Manzikert in 1071. The name Rum was a synonym for the medieval Eastern Roman Empire and its peoples, as it remains in modern Turkish. The name is derived from the Aramaic (romī) and Parthian (frwm) names for ancient Rome, via the Greek Ῥωμαῖοι (Romaioi) meaning Anatolia. It is considered to be the beginning of Turkish history in Anatolia.

The Sultanate of Rum seceded from the Seljuk Empire under Suleiman ibn Qutalmish in 1077. It had its capital first at Nicaea and then at Iconium. It reached the height of its power during the late 12th and early 13th century, when it succeeded in taking key Byzantine ports on the Mediterranean and Black Sea coasts. In the east, the sultanate reached Lake Van. Trade through Anatolia from Iran and Central Asia was developed by a system of caravanserai. Especially strong trade ties with the Genoese formed during this period. The increased wealth allowed the sultanate to absorb other Turkish states that had been established following the conquest of Byzantine Anatolia: Danishmendids, House of Mengüjek, Saltukids, Artuqids.

Lesbos or Lesvos (Greek: Λέσβος, romanized: Lésvos [ˈlezvos]) is a Greek island located in the northeastern Aegean Sea. It has an area of 1,633 km (631 sq mi), with approximately 400 kilometres (249 miles) of coastline, making it the third largest island in Greece and the eighth largest in the Mediterranean. It is separated from Asia Minor by the narrow Mytilini Strait. On the southeastern coast is the island's capital and largest city, Mytilene (Μυτιλήνη), whose name is also used for the island as a whole. Lesbos is a separate regional unit with the seat in Mytilene, which is also the capital of the larger North Aegean region. The region includes the islands of Lesbos, Chios, Ikaria, Lemnos, and Samos. The total population of the island was 83,755 in 2021. A third of the island's inhabitants live in the capital, while the remainder are concentrated in small towns and villages. The largest are Plomari, Agia Paraskevi, Polichnitos, Agiassos, Eresos, Gera, and Molyvos (the ancient Mythimna).

According to later Greek writers, Mytilene was founded in the 11th century BC by the family Penthilidae, who arrived from Thessaly and ruled the city-state until a popular revolt (590–580 BC) led by Pittacus of Mytilene ended their rule. In fact, the archaeological and linguistic records may indicate a late Iron Age arrival of Greek settlers, although references in Late Bronze Age Hittite archives indicate a likely Greek presence then. According to Homer's Iliad, Lesbos was part of the kingdom of Priam, which ruled from Troy. In the Middle Ages, it was under Byzantine and then Genoese rule. Lesbos was conquered by the Ottoman Empire in 1462. The Ottomans then ruled the island until the First Balkan War in 1912, when it became part of the Kingdom of Greece.

The Republic of Venice, officially the Most Serene Republic of Venice and traditionally known as La Serenissima, was a sovereign state and maritime republic with its capital in Venice. Founded, according to tradition, in 697 by Paolo Lucio Anafesto, over the course of its 1,100 years of history it established itself as one of the major European commercial and naval powers. Initially extended in the Dogado area (a territory currently comparable to the Metropolitan City of Venice), during its history it annexed a large part of Northeast Italy, Istria, Dalmatia, the coasts of present-day Montenegro and Albania as well as numerous islands in the Adriatic and eastern Ionian seas. At the height of its expansion, between the 13th and 16th centuries, it also governed Crete, Cyprus, the Peloponnese, a number of Greek islands, as well as several cities and ports in the eastern Mediterranean.

The islands of the Venetian Lagoon in the 7th century, after having experienced a period of substantial increase in population, were organized into Maritime Venice, a Byzantine duchy dependent on the Exarchate of Ravenna. With the fall of the Exarchate and the weakening of Byzantine power, the Duchy of Venice arose, led by a doge and established on the island of Rialto; it prospered from maritime trade with the Byzantine Empire and other eastern states. To safeguard the trade routes, between the 9th and 11th centuries the Duchy waged several wars, which ensured its complete dominion over the Adriatic. Owing to its participation in the Crusades, Venice increasingly penetrated into eastern markets and, between the 12th and 13th centuries, managed to extend its power into numerous eastern emporiums and commercial ports. The supremacy over the Mediterranean Sea led the Republic to the clash with Genoa, which lasted until the 14th century, when, after having risked complete collapse during the War of Chioggia (with the Genoese army and fleet in the lagoon for a long period), Venice quickly managed to recover from the territorial losses suffered with the Treaty of Turin of 1381 and begin expansion on the mainland.

The Duchy of Milan (Italian: Ducato di Milano; Lombard: Ducaa de Milan) was a state in Northern Italy, created in 1395 by Gian Galeazzo Visconti, then the lord of Milan, and a member of the important Visconti family, which had been ruling the city since 1277. At that time, it included twenty-six towns and the wide rural area of the middle Padan Plain east of the hills of Montferrat. During much of its existence, it was wedged between Savoy to the west, Republic of Venice to the east, the Swiss Confederacy to the north, and separated from the Mediterranean by the Republic of Genoa to the south. The duchy was at its largest at the beginning of the 15th century, at which time it included almost all of what is now Lombardy and parts of what are now Piedmont, Veneto, Tuscany, and Emilia-Romagna.

Under the House of Sforza, Milan experienced a period of great prosperity with the introduction of the silk industry, becoming one of the wealthiest states during the Renaissance. From the late 15th century, the Duchy of Milan was contested between the forces of the Habsburg Monarchy and the Kingdom of France. It was ruled by Habsburg Spain from 1556 and it passed to Habsburg Austria in 1707 during the War of the Spanish Succession. The duchy remained an Austrian possession until 1796 when a French army under Napoleon Bonaparte conquered it, and it ceased to exist a year later as a result of the Treaty of Campo Formio, when Austria ceded it to the new Cisalpine Republic.