Origins and early expansion (1108-1448) The town was first mentioned in 1108, at that time known under the name of
Aldenburg. It became important due to its location at a
ford of the navigable Hunte river. Oldenburg became a small county in the shadow of the much more powerful
Free Hanseatic City of Bremen. The earliest recorded inhabitants of the region now called Oldenburg were a
Teutonic people- the
Chauci. The genealogy of the
counts of Oldenburg can be traced to the
Saxon hero
Widukind (opponent of
Charlemagne), but their first historical representative was
Huno of Rustringen (died 1088, founded the monastery of
Rastede in 1059). Huno's descendants appear as
vassals of the dukes of
Saxony and were occasionally rebellious. They were given the title of princes of the Empire when the emperor
Frederick I dismembered the Saxon duchy in 1189. At this time the county of
Delmenhorst formed part of the dominions of the counts of Oldenburg, but afterwards it was on several occasions separated from them to form an
appanage for younger branches of the family, namely in ca. 1266-1436, 1463-1547, and 1577-1617. The northern and western parts of what would become the
Grand Duchy of Oldenburg were in the hands of independent, or semi-independent,
Frisian princes, who were usually
pagan, and the counts of Oldenburg seized much of these lands in a series of wars during the early part of the 13th century. The
Free Hanseatic City of Bremen and the bishop of
Münster also frequently warred with the counts of Oldenburg.
Personal Union with Denmark (1448-1460) In 1448, the 31-year-old
King of Denmark,
Christopher III, died unexpectedly and without heirs. Owing to the
Kalmar Union, he had also been King of Norway and Sweden. The union treaty required the three kingdoms to choose a successor jointly, but tensions between Denmark and Sweden precluded negotiations. When the
Swedish Privy Council allowed
Karl Knutsson to be crowned King of Sweden, the
Danish Privy Council sought an alternative candidate. Their first choice, Duke
Adolf VIII of Schleswig and Holstein, declined but recommended his nephew
Christian, the young Count of Oldenburg, who had been raised at his court. Following Adolf’s recommendation, the Danish Privy Council elected Christian king in September 1448. In 1449 he was also elected
King of Norway, and the two kingdoms were formally united in 1450 with the
Treaty of Bergen. Finally, after the
deposition of Karl Knutsson in 1457, Christian also gained the Swedish crown. During Christian’s early reign, Oldenburg became a Danish exclave. For centuries thereafter, Oldenburg and its rulers would be more closely aligned with Denmark and its foreign policy than with imperial structures or the
Holy Roman Emperors. In Christian’s absence, effective control over the town was left to his brothers,
Gerhard and Moritz, who established a short-lived tyranny.
Independent County (1460-1667) In 1459,
King Christian stood to inherit the
Duchy of Schleswig and the
County of Holstein from his uncle,
Adolf VIII—a development that significantly shaped Oldenburg’s future. To prevent the separation of the two territories, the nobles of Holstein and Schleswig invited Christian to rule as Duke of Schleswig and Count of Holstein. In return, Christian granted the nobles extensive privileges in the
Treaty of Ribe. He also agreed to renounce his hereditary claim to Oldenburg. Christian transferred Oldenburg to his brother
Gerhard, thereby giving Oldenburg independence from the Danish crown. Gerhard waged continual conflicts with the Bishop of Bremen and other neighbors, earning himself a reputation as a pirate in the eyes of the Hanseatic League. In 1483, however, Gerhard was compelled to abdicate in favor of his son, and he later died while on a pilgrimage in Spain. Early in the 16th century, Oldenburg was again enlarged at the expense of the Frisians.
Protestantism was introduced into the county by
Count Anton I (1505–1573), who also suppressed the monasteries. However, he remained loyal to
Charles V during the war of the League of
Schmalkalden, and was able thus to increase his territories, obtaining Delmenhorst in 1547. One of Anton's brothers, Count
Christopher of Oldenburg (c. 1506-1560) also won a reputation as a soldier. Anton's grandson,
Anton Günther (1583–1667), who succeeded in 1603 significantly enlarged and enriched his territories. He thus considered himself the wisest prince who ever had ruled Oldenburg.
Jever had been acquired before his ascension, but in 1624 he added Knipphausen and
Varel to his lands; thus, in 1647 Delmenhorst was finally united. Through neutrality during the
Thirty Years' War and by donating valuable horses to warlord
Count of Tilly, Anton Günther protected his dominions from the devastation levied on nearly all other German states. He also obtained from the emperor the right to levy
tolls on vessels passing along the
Weser, a lucrative grant. In 1607 he erected a
Renaissance castle. Oldenburg was a wealthy town in a time of war and turmoil and its population and power grew considerably.
Danish Oldenburg (1667-1773) Anton Günther, having no legitimate children to keep the main line of his House from going extinct, arranged an agreement with the prospective successors of the county,
King Frederick III of Denmark and Duke
Christian Albrecht of Holstein-Gottorp. It was decided that Oldenburg would pass jointly to them, while Günther’s illegitimate but ennobled son,
Anton von Aldenburg, would serve as governor on their behalf. Upon Günther’s death in 1667, Anton von Aldenburg assumed control of the county, but internal conflicts within the House of Holstein-Gottorp allowed only the Danish crown to assert its inheritance rights effectively. After von Aldenburg’s death in 1680, Danish officials occupied the
residence in Oldenburg, formally integrating the county into Denmark’s administrative system under the authority of the
German Chancellery in Copenhagen. The period of Danish rule was marked by repeated crises. Two
plague outbreaks in 1667 and 1668 decimated the population and weakened the economy, while in 1676 a fire caused by lightning destroyed 700 houses and left 3,000 people homeless. Von Aldenburg’s financial aid did little to accelerate recovery, which was further impeded by the
Scanian War. Danish troops were quartered in Oldenburg and financed partly through local taxation, while their competition for work depressed wages in the town. Following von Aldenburg’s death, reforms were introduced by Chancellor
Christoph Gensch von Breitenau (1681–1701) to modernize local administration and stabilize the economy. Despite these measures, Oldenburg remained a strategic rather than economic asset for Denmark, serving as a military quarter during the
Great Northern War and the
Seven Years’ War at considerable cost to the population. Weak finances also hampered dyke maintenance in the low-lying areas of the county. The
Christmas Flood of 1717 killed more than 4,000 people in Oldenburg and left large tracts of land uncultivable, while the New Year’s Flood of 1720 destroyed many of the emergency dykes erected in the aftermath. King
Frederick IV, who had initiated coastal protection measures in 1714, expanded these efforts after 1717 by granting loans for improved dyke construction. Reconstruction was carried out under the supervision of former admiral
Christian Thomesen Sehested and included the rebuilding of parts of Oldenburg town. Only in the mid-18th century did the county’s economy recover sufficiently to yield a net fiscal benefit to the Danish treasury.
Independence and elevation to duchy (1773-1774) In the 1770s, Oldenburg suddenly stood at the center of European diplomacy. Back in 1544, king
Christian III of Denmark, from the House of Oldenburg, divided the rule over Schleswig and Holstein with his brothers Johann and
Adolf. From Adolf’s branch came the
Dukes of Schleswig-Holstein-Gottorf, who also ruled the
Prince-Bishopric of Lübeck. During the
Great Northern War,
Georg Heinrich von Görtz governed Schleswig and Holstein in the name of the young Duke
Karl Friedrich of Gottorf. Seeking to strengthen his position, he allied with Sweden against Denmark. In response, the Danish king annexed parts of Schleswig in 1713. Karl Friedrich, weakened by this loss, turned to
Russia for support. In 1725 he married
Anna, daughter of
Tsar Peter I. Their son later became
Tsar Peter III in 1762. From the Russian throne he pressed his family’s claims to Schleswig and threatened Denmark with war. But after Peter III’s sudden death only six months later, his widow,
Catherine II, looked for a diplomatic solution. This was achieved in 1773 with the
Treaty of Tsarskoye Selo: Denmark received Schleswig and Holstein, while Oldenburg was transferred to Catherine’s son Paul. He soon passed it on to his great-uncle,
Friedrich August, Prince-Bishop of Lübeck. From that point, Friedrich August ruled Oldenburg as an independent territory, first as Count and, from 1774, as Duke. For Denmark, which was losing its status as a major European power, keeping the small and economically weak Oldenburg was less important than securing its southern border with Schleswig and avoiding conflict with Russia. For the newly independent Oldenburg, dynastic connections to Denmark gradually mattered less, while relationships with the Russian dynasty—and later political ties with
Prussia—became increasingly important. During the reign of Friedrich August, Oldenburg regained its importance as a dynastic residence. Following the destruction of earlier structures, the city was reshaped with new buildings in the
Classical style. ==Rulers==