Thalassocracy

A thalassocracy or thalattocracy (from () , and ; giving ) is a state with primarily maritime realms, an empire at sea, or a seaborne empire. Traditional thalassocracies seldom dominate interiors, even in their home territories. Examples of this were the Phoenician states of Tyre, Sidon and Carthage, and the Italian maritime republics of Venice and Genoa of the Mediterranean; the Chola dynasty of India and the Austronesian states of Srivijaya, the Omani Empire and Majapahit of Maritime Southeast Asia. Thalassocracies can thus be distinguished from traditional empires, where a state's territories, though possibly linked principally or solely by the sea lanes, generally extend into mainland interiors in a tellurocracy ("land-based hegemony").
The term thalassocracy can also simply refer to naval supremacy, in either military or commercial senses. The Ancient Greeks first used the word thalassocracy to describe the government of the Minoan civilization, whose power depended on its navy. Herodotus distinguishes sea-power from land-power and spoke of the need to counter the Phoenician thalassocracy by developing a Greek "empire of the sea".
History and examples of thalassocracies.
Indo-Pacific.
The Austronesian peoples of Maritime Southeast Asia, who built the first ocean-going ships, developed the Indian Ocean's first true maritime trade network. They established trade routes with Southern India and Sri Lanka as early as 1500 BC, ushering in an exchange of material culture (like catamarans, outrigger boats, lashed-lug and sewn-plank boats, and paan) and cultigens (like coconuts, sandalwood, bananas, and sugarcane); as well as connecting the material cultures of India and China. Indonesians in particular traded in spices (mainly cinnamon and cassia) with East Africa, using catamaran and outrigger boats and sailing with the help of the Westerlies in the Indian Ocean. This trade network expanded west to Africa and the Arabian Peninsula, resulting in the Austronesian colonization of Madagascar by the first half of the first millennium AD. It continued into historic times, later becoming the Maritime Silk Road.
The first thalassocracies in the Indo-Pacific region began to emerge around the 2nd century AD, through the rise of emporia exploiting the prosperous trade routes between Funan and India through the Malacca Strait using advanced Austronesian sailing technologies. Numerous coastal city-states emerged, centered on trading ports built near or around river mouths which allowed easy access to goods from inland for maritime trade. These city-states established commercial networks with other trading centers in Southeast Asia and beyond. Their rulers also gradually Indianized by adopting the social structures and religions of India to consolidate their power.
The thalassocratic empire of Srivijaya emerged by the 7th century through conquest and subjugation of neighboring thalassocracies. These included Melayu, Kedah, Tarumanagara, and Medang, among others. These polities controlled the sea lanes in Southeast Asia and exploited the spice trade of the Spice Islands, as well as maritime trade-routes between India and China. Srivijaya was in turn subjugated by Singhasari around 1275, before finally being absorbed by the successor thalassocracy of Majapahit (1293–1527).
Europe and the Mediterranean.
Phoenicia and the Delian League were early examples of Mediterranean thalassocracies.
The Middle Ages saw multiple thalassocracies, often land-based empires which controlled areas of the sea, the most important of them were the Republic of Venice, the Republic of Genoa and the Republic of Pisa. They were know as Maritime republics, controling trade and territories in the Mediterranean Sea for centuries. These contacts were not only commercial, but also cultural and artistic. They also had an essential role in the Crusades. 
The Venetian republic was conventionally divided in the fifteenth century into the "Dogado" of Venice and the Lagoon, the "Stato di Terraferma" of Venetian holdings in northern Italy, and the "Stato da Màr" of the Venetian outlands bound by the sea. According to the French historian Fernand Braudel, Venice was a scattered empire, a trading-post empire forming a long capitalist antenna.
From the 12th to the 15th century the Genoese Republic had the monopoly on the Western Mediterranean trade, establishing colonies and trading posts in numerous countries, and eventually came to control regions in the Black Sea as well. It was also one of the largest naval powers of Europe during the Late Middle Ages.
The Early Middle Ages ( 500 – 1000 AD) saw many of the coastal cities of Southern Italy develop into minor thalassocracies whose chief powers lay in their ports and in their ability to sail navies to defend friendly coasts and to ravage enemy ones. These include the duchies of Gaeta and Amalfi. 
During the 14th and 15th centuries, the Crown of Aragon was also a thalassocracy controlling a large portion of present-day eastern Spain, parts of what is now southern France and other territories in the Mediterranean.
Transcontinental.
With the modern age, the Age of Exploration saw some transcontinental thalassocracies emerge. Anchored in their European territories, several nations established colonial empires held together by naval supremacy. First among them chronologically was the Portuguese Empire, followed soon by the Spanish Empire, which was challenged by the Dutch Empire, itself replaced on the high seas by the British Empire, whose had large landed possessions held together by the greatest navy of its time. With naval arms-races (especially between Germany and Britain), the end of colonialism, and the winning of independence by many colonies, European thalassocracies, which had controlled the world's oceans for centuries, diminished - though Britain's power-projection in the Falklands War of 1982 demonstrated continuing thalassocratic clout.
The Ottoman Empire expanded from a land-based region to dominate the Eastern Mediterranean and to expand into the Indian Ocean as a thalassocracy from the 15th century AD.