Croatia in the context of "Pannonia"

The Adriatic Sea (/ˌeɪdriˈætɪk/) is a body of water separating the Italian Peninsula from the Balkan Peninsula. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Sea) to the northwest and the Po Valley. The countries with coasts on the Adriatic are Albania, Bosnia and Herzegovina, Croatia, Italy, Montenegro, and Slovenia.

The Adriatic contains more than 1,300 islands, mostly located along its eastern coast. It is divided into three basins, the northern being the shallowest and the southern being the deepest, with a maximum depth of 1,233 metres (4,045 ft). The prevailing currents flow counterclockwise from the Strait of Otranto. Tidal movements in the Adriatic are slight, although larger amplitudes occur occasionally. The Adriatic's salinity is lower than the Mediterranean's because it collects a third of the fresh water flowing into the Mediterranean, acting as a dilution basin. The surface water temperatures generally range from 30 °C (86 °F) in summer to 12 °C (54 °F) in winter, significantly moderating the Adriatic Basin's climate. The Adriatic Sea sits on the Apulian or Adriatic Microplate. In the Late Oligocene, the Italian Peninsula first formed, separating the Adriatic Basin from the rest of the Mediterranean. The western coast is alluvial or terraced, while the eastern coast is highly indented with pronounced karstification. There are dozens of marine protected areas in the Adriatic, designed to protect the sea's habitats and biodiversity—more than 7,000 species are identified as native to the Adriatic, many of them endemic, rare and threatened ones.

Montenegro is a country in Southeast Europe, on the Balkan Peninsula. Its 25 municipalities have a total population of 633,158 people in an area of 13,883 km (5,360 sq mi). It is bordered by Serbia to the northeast, Bosnia and Herzegovina to the northwest, Kosovo to the east, Albania to the southeast, and Croatia to the west, and has a coastline along the Adriatic Sea to the southwest. The capital and largest city is Podgorica, while Cetinje is the Old Royal Capital and cultural centre.

Before the arrival of the Slav peoples in the Balkans in the 6th and 7th centuries CE, the area now known as Montenegro was inhabited principally by people known as Illyrians.During the Early Medieval period, three principalities were located on the territory of modern-day Montenegro: Duklja, roughly corresponding to the southern half; Travunia, the west; and Rascia proper, the north. The Principality of Zeta emerged in the 14th and 15th centuries. From the late 14th century to the late 18th century, large parts of southern Montenegro were ruled by the Venetian Republic and incorporated into Venetian Albania. The name Montenegro was first used to refer to the country in the late 15th century. After falling under Ottoman Empire rule, Montenegro gained semi-autonomy in 1696 under the rule of the House of Petrović-Njegoš, first as a theocracy and later as a secular principality. Montenegro's independence was recognised by the Great Powers at the Congress of Berlin in 1878. In 1910, the country became a kingdom. After World War I, the kingdom became part of Yugoslavia. Following the breakup of Yugoslavia, the republics of Serbia and Montenegro together proclaimed a federation. In June 2006 Montenegro declared its independence following a referendum.

The Ardiaei were an Illyrian people who resided in the territory of present-day Bosnia and Herzegovina, Albania, Kosovo, Montenegro, and Croatia between the Adriatic coast on the south, Konjic on the north, along the Neretva river and its right bank on the west, and extending to Lake Shkodra to the southeast. From the 3rd century BC to 168 BC the capital cities of the Ardiaean State were Rhizon and Scodra.

The Ardiaean kingdom was transformed into a formidable power—both on land and sea—under the leadership of Agron of Illyria. During this time, Agron captured parts of Epirus, Corcyra, Epidamnos, and Pharos in succession, establishing garrisons there. The Ardiaean realm became one of Rome's major enemies, and the primary threat to it in the Adriatic Sea. A series of wars were fought between the Roman Republic and the Illyrian (Ardiaean-Labaeatan) kingdom in the 3rd–2nd centuries BC. Polybius (203 BC–120 BC) wrote that they were subdued by the Romans in 229 BC. The Epitome of Livy reports the Roman consul Fulvius Flaccus put down an uprising in 135 BC undertaken by Ardiaei and Pleraei in Roman Illyria.

Serbia, officially the Republic of Serbia, is a landlocked country in Southeast and Central Europe. Located in the Balkans, it borders Hungary to the north, Romania to the northeast, Bulgaria to the southeast, North Macedonia to the south, Croatia to the northwest, Bosnia and Herzegovina to the west, and Montenegro to the southwest. Serbia also claims to share a border with Albania through the disputed territory of Kosovo. Serbia has about 6.6 million inhabitants, excluding Kosovo. Serbia's capital, Belgrade, is also the largest city in the country.

Continuously inhabited since the Paleolithic age, the territory of modern-day Serbia faced Slavic migrations in the 6th century. Several regional states were founded in the Early Middle Ages and were at times recognised as tributaries to the Byzantine, Frankish and Hungarian kingdoms. The Serbian Kingdom obtained recognition by the Holy See and Constantinople in 1217, reaching its territorial apex in 1346 as the Serbian Empire. By the mid-16th century, the Ottoman Empire annexed the entirety of modern-day Serbia; their rule was at times interrupted by the Habsburg Empire, which began expanding towards Central Serbia from the end of the 17th century while maintaining a foothold in Vojvodina. In the early 19th century, the Serbian Revolution established the nation-state as the region's first constitutional monarchy, which subsequently expanded its territory.

The Slavs or Slavic people are a major ethnic group in Europe. They speak Slavic languages and preserve Slavic culture. There are 13 Slavic countries in Europe, which include: Poland, the Czech Republic, Slovakia, Russia, Belarus, Ukraine, Slovenia, Croatia, Bosnia and Herzegovina, Serbia, Montenegro, North Macedonia, and Bulgaria; the Slavs comprise a population of around 300 million people. There are three different Slavic ethnic groups: the West Slavs, the East Slavs, and the South Slavs; the Poles, Silesians, Kashubians, Sorbs, Czechs, and Slovaks are West Slavs; Russians, Belarusians, Ukrainians, and Rusyns are East Slavs; while Slovenes, Resians, Croats, Bosniaks, Serbs, Montenegrins, Torlakians, the Gorani, the Torbeši, Macedonians, and Bulgarians are South Slavs. Slavs are geographically distributed throughout the northern parts of Eurasia; they predominantly inhabit Central Europe, Eastern Europe, Southeastern Europe, and Northern Asia, though there is a large Slavic minority scattered across the Baltic states and Central Asia, and a substantial Slavic diaspora in the Americas, Western Europe, and Northern Europe.

Early Slavs lived during the Migration Period and the Early Middle Ages (approximately from the 5th to the 10th century AD), and came to control large parts of Central, Eastern, and Southeast Europe between the sixth and seventh centuries. Beginning in the 7th century, they were gradually Christianized. By the 12th century, they formed the core population of a number of medieval Christian states: East Slavs in the Kievan Rus', South Slavs in the Bulgarian Empire, the Principality of Serbia, the Duchy of Croatia and the Banate of Bosnia, and West Slavs in the Principality of Nitra, Great Moravia, the Duchy of Bohemia, and the Kingdom of Poland.

Southern Europe is also known as Mediterranean Europe, as its geography is marked by the Mediterranean Sea. Definitions of southern Europe include some or all of these countries and regions: Albania, Andorra, Bosnia and Herzegovina, Bulgaria, Croatia, Cyprus, Gibraltar, Greece, Italy, Kosovo, Malta, Monaco, Montenegro, North Macedonia, Portugal, San Marino, Serbia, Slovenia, southern France, southern Romania, Spain, Ticino (Switzerland), Turkey, and Vatican City.

Southern Europe is focused on the three peninsulas located in the extreme south of the European continent. These are the Iberian Peninsula, the Italian Peninsula, and the Balkan Peninsula. These three peninsulas are separated from the rest of Europe by towering mountain ranges, respectively by the Pyrenees, the Alps and the Balkan Mountains. The location of these peninsulas in the heart of the Mediterranean Sea, as well as their mountainous reliefs, provide them with very different types of climates (mainly subtropical Mediterranean) from the rest of the continent. So, the Sirocco hot wind that originates in the heart of the Sahara blows over Italy, going up to the interior of the Alpine arc (Po Valley). The Alps prevent the Sirocco from spreading to the rest of Europe. And, conversely, the Alps and the Pyrenees protect the Italian and Iberian Peninsulas from the rains and icy winds from the south of France such as the Mistral and the Tramontane. When the Mistral and the Tramontane are blowing, this provokes an "upwelling" phenomenon on the French coast. They push the surface waters out to sea and bring deeper, cooler waters up to the seaside. Consequently, the temperature of the waters of the French coasts are therefore very cool even in summer, and not representative of the rest of the Mediterranean.This same kind of phenomenon takes place between the two slopes of the Balkan mountain range. These mountains have, moreover, been a serious handicap to population displacement, focusing southern Europe mainly on the Mediterranean world. The climate and cultures are therefore very specific.

The European Union (EU) has expanded a number of times throughout its history by way of the accession of new member states to the Union. To join the EU, a state needs to fulfil economic and political conditions called the Copenhagen criteria (named after the Copenhagen summit in June 1993), which require a stable democratic government that respects the rule of law, and its corresponding freedoms and institutions. According to the Maastricht Treaty, each current member state and the European Parliament must agree to any enlargement. The process of enlargement is sometimes referred to as European integration. This term is also used to refer to the intensification of co-operation between EU member states as national governments allow for the gradual harmonisation of national laws.

The EU's predecessor, the European Economic Community, was founded with the Inner Six member states in 1958, when the Treaty of Rome came into force. Since then, the EU's membership has grown to twenty-seven, with the latest member state being Croatia, which joined in July 2013. The most recent territorial enlargement of the EU was the incorporation of Mayotte in 2014. Campione d'Italia joined the EU Customs Union in 2020. The most notable territorial reductions of the EU, and its predecessors, have been the exit of Algeria upon independence in 1962, the exit of Greenland in 1985, and the withdrawal of the United Kingdom in 2020.

San Marino, officially the Republic of San Marino (RSM), is a landlocked country in Southern Europe, completely surrounded by Italy. Located on the northeastern slopes of the Apennine Mountains, it is the larger of two microstates within Italy, the other being Vatican City. San Marino is the fifth-smallest country in the world, with a land area of just over 61 km (23.5 mi) and a population of 34,042 as of 2025. Its capital, the City of San Marino, sits atop Monte Titano, while its largest settlement is Dogana, in the municipality of Serravalle.

San Marino claims to have been founded in AD 301 and to be the oldest extant sovereign state and the oldest constitutional republic. It is named after Saint Marinus, a stonemason from the Roman island of Rab (in present-day Croatia), who is supposed in mythic accounts to have established a monastic community on Monte Titano. The country has a rare constitutional structure: the Grand and General Council, a democratically elected legislature, selects two heads of state, the Captains Regent, every six months. They are chosen from opposing political parties, and serve concurrently with equal powers and preside over several institutions of state, including the Grand and General Council. Only the Federal Council of Switzerland also follows that structure, except with seven heads of state, and different responsibilities and functions.

Italian (italiano, pronounced [itaˈljaːno] , or lingua italiana, pronounced [ˈliŋɡwa itaˈljaːna]) is a Romance language of the Indo-European language family. It evolved from the colloquial Latin of the Roman Empire, and is the least divergent language from Latin, together with Sardinian. It is spoken by 68 to 85 million people, including 64 million native speakers as of 2024. Some speakers of Italian are native bilinguals of both Italian (either in its standard form or regional varieties) and a local language of Italy, most frequently the language spoken at home in their place of origin.

Italian is an official language in Italy, San Marino, Switzerland (Ticino and the Grisons), and Vatican City, and it has official minority status in Croatia, Slovenia (Istria), Romania, Bosnia and Herzegovina, and in 6 municipalities of Brazil. It is also spoken in other European and non-EU countries, most notably in Malta (by 66% of the population), Albania and Monaco, as well as by large immigrant and expatriate communities in the Americas, Australia and on other continents.

The Italian geographic region, Italian physical region or Italian region is a geographical region of Southern Europe delimited to the north by the mountain chains of the Alps. This subregion is composed of a peninsular and continental part and an insular part. Located between the Balkan Peninsula and the Iberian Peninsula, it protrudes into the centre of the Mediterranean Sea and overlooks the Adriatic Sea, the Ionian Sea, the Ligurian Sea, the Sardinian Channel, the Sea of Corsica, the Sea of Sardinia, the Strait of Sicily, and the Tyrrhenian Sea.

The Italian geographic region, in its traditional and most widely accepted extent, has an area of approximately 324,000 square kilometres (125,000 sq mi), which is greater than the area of the entire Italian Republic (301,230 square kilometres (116,310 sq mi)). The region also includes territories that are sovereign parts of Croatia, France, Slovenia, and Switzerland, as well as the four small sovereign states of the Principality of Monaco, the Republic of Malta, the Republic of San Marino, and the Vatican City State (the Holy See).