The Ugaunians (ugalased in Estonian) is one of the Finnic tribes that were called Chudes in Russian and that later formed the Estonian nation. They lived in the province of Ugaunia (also Ugania, Ungannia) in what is now Tartu, Põlva, Võru and Valga County counties of Estonia. They are usually associated with speakers of Võru dialect of Estonian language.

In modern Estonian literature, province of Ugaunia is called Ugandi or Ugala. The name Ugandi is derived by associating Ugaunia with the name of Uandimägi Hill near Otepää.

The power center of Ugaunians was the Fort Bear's Head ( Caput Ursi in Latin, Medvezh'ya Golova in Russian, Oden Peh in old Estonian, present Linnamägi Hill in the city of Otepää ). The hill was indeed shaped like a head of a bear. Bear was probably holy animal for Ugaunians.

Another important stronghold was Tharbata in the river Mother of Waters (Emajõgi ).

The name Ugaunia probably comes from Slavic language word Ug, meaning South (cf. Yugoslavia).

In Latvian, the country of Estonia is still called Igaunia after Ugaunians, their ancient warlike neighbors.

In Estonian folklore, Ugaunians (ugalased) are enemy warriors and robbers. For example, a folk song from Viljandi County calls for speeding up the harvest work because Ugaunians might attack. "Ugalane" has also been used as a disparaging word for an unsophisticated country person.

Due to its location, Ugaunia always bore brunt of Russian attacks against Chudes, as they called Finnic peoples around their North-Eastern border. In 1030 Tharbata was conquered by Kievan Prince Yaroslav the Wise who made Ugaunians his subjects and built there a town he named St.George (Yuriev). Kievan rule lasted until 1061 when Tharbata/Yuriev was burned down by 'Sosols' (probably Sackalians ).

Rulers of Novgorod and Pskov made frequent raids against Ugaunians in 12th century but never succeeded to subjugate them. Fort Bear's Head was conquered in 1116 and 1193, Tharbata in 1134 and 1192. Also Ugaunians made several raids against Pskov.

In the beginning of 13th century, new powerful enemy appeared. German crusaders had established foothold at the mouth of Duna river and started to expand and christen local tribes. Ugaunian southern neighbors Letts saw crusaders as potential allies against their traditional adversaries. Ugaunians wanted to continue truce with their new neigbors, but crusaders had list of preconditions. They demanded Ugaunians to pay reparation for an old incident. Many years ago Ugaunians upon the advice of the Livonians had robbed a caravan of German merchants by the Duna river.

In 1207 the crusaders sent priest Alabrand to Ugaunia to demand compensation, but did not receive any answer. Next year the Letts and Livonian Brothers of the Sword sent a new delegation to Ugaunia and returned with Ugaunian envoys. Ugaunians were offered "eternal peace" if they accept Christianity and return everything they had robbed from Germans and Letts. Ugaunians refused and left, threatening the Letts with "very sharp lances".

The crusaders and Letts went to war against Ugaunians. They burned the Fort Bear's Head and returned with captives and booty. Ugaunians and Sackalians retaliated, raided territories of the Letts and burned their worst enemies alive. The Livonians and the Bishop of Riga wanted the peace and sent the priest Alabrand to Fort Bear's Head to negotiate. Alabrand used the gathering of Ugaunians to preach the Christianity to them. Some pagan Ugaunians wanted to kill him because of his preaching, but his status as the messenger of the bishop protected him. Ugaunians made the peace with Bishop of Riga, the leader of the Livonian crusade .

In 1210 the Novgorodian prince Mstislav and his brother, Vladimir the prince of Polotsk sent army against Ugaunians. They besieged the Fort Bear's Head and fought there eight days. Defenders of the Fort Bear's head suffered the shortage of food and water and were forced to ask for peace. Ugaunians had to accept Orthodox baptism and pay tribute of 400 "nogata" marks. (Nogat or nahad is Estonian word for pelts).

The same summer Ugaunians of Fort Bear's Head surrendered to crusader commander Bertold of Wenden. Ugaunians continued to raid Lettish territories. Wars between Ugaunians and Letts lasted the whole decade. The elders of Ugaunians and Letts had deep personal feuds. When Ugaunians captured Thalibald of Tricatea in 1215 and burned him alive, his sons burned alive all Ugaunian men they could catch to avenge. They also tortured Ugaunians to force them to show hiding places in the woods.

When all Ugaunian provinces were burnt down, the people still alive sent messengers to Riga, asking for peace and promised to receive the baptism. They told that all who had been involved of the robbery of German merchants had already been killed. The priests Otto and Peter Kakuwalda were sent to baptize them.

Hearing about that, Russian prince Vladimir of Pskov attacked Ugaunians. Ugaunians and German crusaders fortified Fort Bear's Head and avenged Russians, raiding lands of Pskov and Novgorod. After that Ugaunians went with crusaders, Livonians and Letts against Estonian pagan provinces Jerwia and Vironia. Prince Vladimir of Pskov sent messenger through all the Estonia to besiege Germans and Ugaunians at Fort Bear's Head. Harrians and Oeselians came and even already baptized Sackalians.

While troops of 20000 of Russians and Oeselians attacked the Fort Bear's Head, Ugaunians made with crusaders raids against Novgorod, Vironians and Votians.

In 1220 Ugaunians rebelled against Germans. Sackalians sent bloody swords with which they had killed Germans to Ugaunians of Tharbata and Fort Bear's Head. In Tharbata they decided by lot whether to sacrifice to the gods an ox or their priest Hartwig, who was equally fat. Lucklily for the priest, the lot fell upon the ox.

Ugaunians decided to side with Novgorodians. Russian princes of Pskov, Novgorod and Suzdal sent huge Russian troops of 20000 men to Ugaunia. The people of Tharpata sent them large gifts and Bear's Head welcomed them too. Russian left Vyachko (Vetseke) as their prince to rule Ugaunians and other Estonian provinces. Russians gathered tax from provinces around.

In 1224 crusaders retook all Estonian provinces. After casting lot, bishop Hermann of Buxhoeveden was given rule over Ugaunia while Sackala was given to the order. Fort Bear Head was happy over the rule of bishop Hermann but Tharbata was still ruled by Vetseke and his Russians. Later 1224 however, Tharbata was conquered and all its Ugaunian and Russian defenders killed.

Bishop Hermann started to fortify Bear Head and Tharpata. He chose Tharbata/Dorpat to be his residence. Bishop Hermann and his Ugaunian subjects fought frequently against Novgorod and were defeated by prince Alexander Nevsky in the Battle on the Ice 1242.

Ugaunia became known as the Bishopric of Dorpat.