The Duchy of Tridentum was an autonomous Lombard

Lombards

The Lombards , also referred to as Longobards, were a Germanic tribe of Scandinavian origin, who from 568 to 774 ruled a Kingdom in Italy...

 duchy, established by Euin

Euin

Euin , also Ewin or Eoin, was the first Lombard Duke of Trent during the Rule of the Dukes, an interregnum during which the Kingdom of Italy was ruled by its regional magnates, the dukes of the thirty or so cities. Euin participated in several significant wars during his long reign...

 during the Lombard interregnum of 574–584

Rule of the Dukes

The Rule of the Dukes was an interregnum in the Lombard Kingdom of Italy during which Italy was ruled by the Lombard dukes of the old Roman provinces and urban centres...

 that followed the assassination of the Lombard leader Alboin

Alboin

Alboin was king of the Lombards from about 560 until 572. During his reign the Lombards ended their migrations by settling in Italy, the northern part of which Alboin conquered between 569 and 572...

. The stronghold of Euin's territory was the Roman city of Tridentum in the upper valley of the Adige

Adige

The Adige is a river with its source in the Alpine province of South Tyrol near the Italian border with Austria and Switzerland. At in length, it is the second longest river in Italy, after the River Po with ....

, in the foothills of the Alps

Alps

The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....

 in northern Italy, where the duchy formed one of the marches

Marches

A march or mark refers to a border region similar to a frontier, such as the Welsh Marches, the borderland between England and Wales. During the Frankish Carolingian Dynasty, the word spread throughout Europe....

 of the Lombard Kingdom of Italy

Kingdom of the Lombards

The Kingdom of the Lombards or Lombard Kingdom was an early medieval state, with its capital in Pavia, established by the Lombards on the Italian Peninsula between 568-569 and 774 .Effective control by the rulers of both the major areas that constituted the...

. There he shared power with the bishop, who was nominally subject to the Patriarch of Aquileia

Patriarch of Aquileia

The Patriarch of Aquileia was an office in the Roman Catholic Church. During the Middle Ages the Patriarchate of Aquileia was a temporal state in Northern Italy. The Patriarchate of Aquileia as a church office was suppressed in 1752....

. In 574–75, Lombard raiding parties pillaged the valley of the Rhône, incurring retaliatory raids into the duchy by Austrasian Franks

Austrasia

Austrasia formed the northeastern portion of the Kingdom of the Merovingian Franks, comprising parts of the territory of present-day eastern France, western Germany, Belgium, Luxembourg and the Netherlands. Metz served as its capital, although some Austrasian kings ruled from Rheims, Trier, and...

, who had seized control of the mountain passes leading into the kingdom of Burgundy

Kingdom of Burgundy

Burgundy is a historic region in Western Europe that has existed as a political entity in a number of forms with very different boundaries. Two of these entities - the first around the 6th century, the second around the 11th century - have been called the Kingdom of Burgundy; a third was very...

. Euin was at the head of the army loyal to Authari

Authari

Authari also known as Agilolf, was king of the Lombards from 584 to his death. After his father, Cleph, died in 574, the Lombardic nobility refused to appoint a successor, resulting in ten years interregnum known as the Rule of the Dukes.In 574 and 575 the Lombards made the blunder of invading...

 that went into the territory of the duke of Friuli

Duchy of Friuli

The Duchy of Friuli was one of the great territorial Lombard duchies, the first to be established. It was an important buffer between the Lombard kingdom of Italy and the Slavs...

 in Istria

Istria

Istria , formerly Histria , is the largest peninsula in the Adriatic Sea. The peninsula is located at the head of the Adriatic between the Gulf of Trieste and the Bay of Kvarner...

, c 589, and he was sent by Agilulf

Agilulf

Agilulf called the Thuringian, was a duke of Turin and king of the Lombards from 591 until his death.-Biography:A relative of his predecessor Authari, he was selected king on the advice of the Christian queen and widow of Authari, Theodelinda, whom he then married...

 to make peace with the Franks his neighbors, in 591. After Euin's death c 595, Agilulf installed Gaidoald

Gaidoald

Gaidoald was the second Lombard Duke of Trent. He was assigned to Trent on the death of Euin in January 595. He was described by Paul the Deacon as "a good man and a Catholic in religion" in his Historia Langobardorum. In 602 or 603, Gaidoald and fellow duke Gisulf I of Friuli made peace with king...

, who was a Catholic, rather than an Arian Christian

Arianism

Arianism is the theological teaching attributed to Arius , a Christian presbyter from Alexandria, Egypt, concerning the relationship of the entities of the Trinity and the precise nature of the Son of God as being a subordinate entity to God the Father...

. After some friction between king and duke, they were reconciled in 600. The separate Lombard duchy of Brescia was united with Tridentum in the person of Alagis, a fervent Arian and opponent of the Lombard king, Perctarit

Perctarit

Perctarit was king of the Lombards from 661 to 662 the first time and later from 671 to 688. He was the son and successor of Aripert I. He shared power with his brother Godepert. He was a Catholic, Godepert an Arian. He ruled from Milan, Godepert from Pavia...

, who was killed in the battle of Cornate d'Adda

Cornate d'Adda

Cornate d'Adda is a comune in the Province of Monza and Brianza in the Italian region Lombardy, located about 30 km northeast of Milan and 20 km from Monza.-External links:*...

 (688).

With the collapse of the Lombard kingdom in 773–74, the duchy of Tridentum passed into Frankish

Carolingian Empire

Carolingian Empire is a historiographical term which has been used to refer to the realm of the Franks under the Carolingian dynasty in the Early Middle Ages. This dynasty is seen as the founders of France and Germany, and its beginning date is based on the crowning of Charlemagne, or Charles the...

 control and was transformed. After German king Otto I

Otto I, Holy Roman Emperor

Otto I the Great , son of Henry I the Fowler and Matilda of Ringelheim, was Duke of Saxony, King of Germany, King of Italy, and "the first of the Germans to be called the emperor of Italy" according to Arnulf of Milan...

 had subdued the Italian kingdom

Kingdom of Italy (medieval)

The Kingdom of Italy was a political entity under control of Carolingian dynasty of Francia first, after the defeat of the Lombards in 774. It was finally incorporated as a part of the Holy Roman Empire in 962....

 in 952 he incorporated Tridentum into the March of Verona

March of Verona

The March of Verona and Aquileia was a vast march in northeastern Italy during the Middle Ages, centered on the cities of Verona and Aquileia. Except for Venice, it included the territories of the modern-day regions of Veneto and Friuli-Venezia Giulia as well as Istria and Trentino up to the Adige...

. Its strategic position controlling the Alpine mountain pass

Principal passes of the Alps

This article lists the principal mountain passes and tunnels in the Alps, and gives a history of transport across the Alps.-Main chain:From west to east:-Other passes:Detailed lists of passes are given by Alpine subdivision, see the following articles:...

es encouraged the eleventh-century Holy Roman Emperor

Holy Roman Emperor

The Holy Roman Emperor is a term used by historians to denote a medieval ruler who, as German King, had also received the title of "Emperor of the Romans" from the Pope...

s to invest the Bishop Ulrich II of Trent

Bishopric of Trent

The Bishopric of Trent is a former ecclesiastical territory roughly corresponding to the present-day Northern Italian autonomous province of Trentino. It was created in 1027 and existed until 1802, when it was secularised and absorbed into the County of Tyrol held by the House of Habsburg...

 with temporal powers over a sizable territory, as an independent prince of the Empire

Holy Roman Empire

The Holy Roman Empire was a realm that existed from 962 to 1806 in Central Europe.It was ruled by the Holy Roman Emperor. Its character changed during the Middle Ages and the Early Modern period, when the power of the emperor gradually weakened in favour of the princes...

, with the powers and privileges of a duke. A succession of Prince-Bishop

Prince-Bishop

A Prince-Bishop is a bishop who is a territorial Prince of the Church on account of one or more secular principalities, usually pre-existent titles of nobility held concurrently with their inherent clerical office...

s ruled, except for a few short intervals, until 1802, when the bishopric was secularized

German Mediatisation

The German Mediatisation was the series of mediatisations and secularisations that occurred in Germany between 1795 and 1814, during the latter part of the era of the French Revolution and then the Napoleonic Era....

 and became a part of Austrian Tyrol

County of Tyrol

The County of Tyrol, Princely County from 1504, was a State of the Holy Roman Empire, from 1814 a province of the Austrian Empire and from 1867 a Cisleithanian crown land of Austria-Hungary...

.