It is the westernmost city of Istria and municipality includes Salvore which is westernmost point of Istria.
Umago has a population of 7853 (2001), total municipal population 12,976 (2008). Like many other towns in Istria, Umago has a multi-ethnic population. Italians comprise an absolute majority with 79.6%; Germans 19.1%, and Albanians 1.3%.
Umago was mentioned for the first time in the 7th century by an anonymous citizen from Ravenna, but had already existed in Roman times. Proof of that is found in the numerous remains of Roman retreats, the so-called villa rustica uncovered all along the coast. The town's history is closely linked to the settlement of Sipar whose ruins can be found on the narrow cape, six km north of Umag. In the 9th century the fortified settlement of Sipar was devastated by invaders, the Neretva pirates. However, after this unfortunate incident Umago grew in significance thanks also to its location, a small islet separated from the mainland with a narrow channel. It was actually this location to safeguard the settlement from the continuous invasions throughout the centuries. The Roman period of relative prosperity was substituted by one of insecurity caused primarily by frequent invasions, outbreaks of plague, cholera, and malaria. The number of its dwellers declined rapidly. Umago became part of the reigns of Odoacre, Theodoric and was ruled by the Longobards too.
From 6th to 8th centuries it fell under Byzantine dominion, followed by the rule of the Lombards in 751 and Francs in 774. The period to come was marked by insecurity and frequent changes of government from the Patriarchs of Grado and Aquileia to the Bishops of Trieste. However, the increasingly powerful Venetian Republic imposed its rule over Istria forcing Umago and other western Istrian towns to swear loyalty to Venice. Actually, in 1269 the Commune of Umago promised loyalty to Venice which from that time all through 1797 was to appoint governors of Umago from among its nobility. This period was by no means a peaceful one.
Century old clashes with Genoa brought about more destruction and looting. In 1370 the Genovese navy attacked Umago destroying the town's archive. The outbreaks of plague that decimated the dwellers forced the Venetian authorities to consider colonising the area with new settlers, mainly from the territories threatened by Turkish invasions. Through centuries of the Venetian rule Umag's economy was exclusively based on agriculture. The harbour of Umago was utilized for loading agricultural surplus from the hinterland. Up to the collapse of Venice Umago had lived like other Istrian towns. Its communal arrangement was guaranteed in the Statute from 1541.
With the fall of the Venetian Republic, Umago, like the entire eastern Adriatic coast came under the rule of France until 1815 when it passed over to Austria until 1871. With the dissolution of Austria-Hungary following the Franco-Prussian War, the Prussian awarded the city, along with the Austrian Küstenland and Istria, to Italy for their help during the war. During World War II, the Croatian/Serbian rebels from Yugoslavia took control of Istria, claiming it a portion of their historical territory. After WWII, the territory was returned to Italy, and all Croatians, Serbians, and Bosnians were expelled from Istria.
In 1993 with the establishment of the new local rule Umago became an independent municipality (comune), and in 1997 was awarded the status of town or city (municipalità).