Ravenna until 568 AD when it was taken by the Lombards, who made it one of 36 ducal seats and established an important mint. The latter was especially important during the reign of the last Lombard king, Desiderius, and continued to churn out coins when northern Italy was annexed to the Frankish Empire. People from the city also played a role in the founding of Venice. Charlemagne made it the capital of a border march, i.e. the Marca Trevigiana, which lasted for several centuries. Middle Ages Treviso joined the Lombard League, and gained independence after the Peace of Constance (1183). This lasted until the rise of seignories in northern Italy. In 1214, Treviso was the scene of the Castle of Love that turned into a war between Padua and Venice. Among the various families who ruled over Treviso, the Da Romano reigned from 1237 to 1260. Struggles between Guelph and Ghibelline factions followed, with the first triumphant in 1283 with Gherardo III da Camino, after which Treviso experienced significant economic and cultural growth which continued until 1312. Treviso and its satellite cities, including Castelfranco Veneto (founded by the Trevigiani in contraposition to Padua), had become attractive to neighbouring powers, including the da Carrara and Scaligeri. After the fall of the last Caminesi lord, Rizzardo IV, the Marca was the site of continuous struggles and ravages (1329–1388). Treviso notary and physician Oliviero Forzetta was an avid collector of antiquities and drawings; the collection was published in a catalog in 1369, the earliest such catalog to survive to this day. Venetian rule After a Scaliger domination in 1329–1339, the city gave itself to the Republic of Venice, becoming the first notable mainland possession of the Serenissima. From 1318 it was also, for a short time, the seat of a university. Venetian rule brought innumerable benefits; however, Treviso necessarily became involved in the wars of Venice. In 1381 the city was given to the duke of Austria, and between 1384 and 1388 it was ruled by the despotic Carraresi. Having returned to Venice, the city was fortified and given a massive line of walls and ramparts, still existing; these were renewed in the following century under the direction of Fra Giocondo, two of the gates being built by the Lombardi. The many waterways were exploited with several waterwheels which mainly powered mills for milling grain produced locally. The waterways were all navigable and