Venice developed into a city state between the 9th and the 12th Centuries among three other city states in Italy: Pisa, Genoa and Amalfi. Venice became a major naval power, exerting influence over commercial activity throughout Europe, thanks to its strategic location at the head of the Adriatic Sea. It became the centre of trade between Western Europe and other regions of the world, such as Asia.

Construction of the Venetian Arsenal shipyard began in the early 12th Century. In 1178, control of the alpine Brenner Pass passed from Verona to Venice, which enabled import of silver from Germany. By 1200, Venice had taken control of the eastern shores of the Adriatic Sea, primarily for commercial reasons, but piracy in the region was a threat to trade. Later, some mainland possessions that extended westward to the Adda River came to be known as the Lombard districts of the Terraferma, which were acquired to guarantee alpine trade arteries, serve as defensive territory and ensure supply of wheat.

Venice gained control over many islands in the Aegean Sea, including Crete and Cyprus, and became influential also in the Middle East. After the Fourth Crusade, the city became an imperial power, playing a key role in the capture of Constantinople in 1204. As the short-lived Latin Empire was established, Venice, in turn, founded the Duchy of the Archipelago, which came to the fore.

By the early 14th Century, crossbow practice had become mandatory in Venice for citizens. However, weapons became more expensive and difficult to operate, and professional troops were hired to assist operations on merchant vessels and to row in galleys. Venice’s Army soon matched its formidable Navy. Whereas most city states in Italy were hiring mercenary troops by the 1200s, Venetian soldiers were still recruited from the lagoon. In times of emergency, all men between 17 and 60 years of age were compelled to serve in the Army. According to a register from 1338, about 30,000 Venetian men were able to bear arms. Aristocrats and other rich men served in the cavalry, while conscripts were assigned to the infantry.