The Treaty of Åbo or the Treaty of Turku was a peace treaty

Treaty

A treaty is an express agreement under international law entered into by actors in international law, namely sovereign states and international organizations. A treaty may also be known as an agreement, protocol, covenant, convention or exchange of letters, among other terms...

 signed between the Russian Empire

Russian Empire

The Russian Empire was a state that existed from 1721 until the Russian Revolution of 1917. It was the successor to the Tsardom of Russia and the predecessor of the Soviet Union...

 and Sweden in Turku

Turku

Turku is a city situated on the southwest coast of Finland at the mouth of the Aura River. It is located in the region of Finland Proper. It is believed that Turku came into existence during the end of the 13th century which makes it the oldest city in Finland...

  on 7. August^jul./ 18. August^greg. 1743 in the end of the Russo-Swedish War of 1741-1743.

By the end of the war, the Imperial Russian Army

Imperial Russian Army

The Imperial Russian Army was the land armed force of the Russian Empire, active from around 1721 to the Russian Revolution of 1917. In the early 1850s, the Russian army consisted of around 938,731 regular soldiers and 245,850 irregulars . Until the time of military reform of Dmitry Milyutin in...

 had occupied most of Finland, prompting Field-Marshal Trubetskoy

Trubetskoy

Trubetskoy , Трубецкой , Трубяцкі , Trubecki , Trubetsky , Трубецький , Troubetzkoy , Trubezkoi or Trubetzkoy , is a Ruthenian Gediminid gentry family of Black Ruthenian stock, like many other princely houses of Grand Duchy of Lithuania, later prominent in Russian...

 and Chancellor Aleksey Bestuzhev to demand the application of uti possidetis

Uti possidetis

Uti possidetis is a principle in international law that territory and other property remains with its possessor at the end of a conflict, unless otherwise provided for by treaty; if such a treaty doesn't include conditions regarding the possession of property and territory taken during the war,...

 principle in this case. By acquiring Finland, Russian politicians aspired to move the Swedish border considerably to the north, thus reducing the danger of Swedish attack on the Russian capital, Saint Petersburg

Saint Petersburg

Saint Petersburg is a city and a federal subject of Russia located on the Neva River at the head of the Gulf of Finland on the Baltic Sea...

. In the hope of gaining independence, the Finnish estates offered the ephemeral throne

Kingdom of Finland (1742)

The attempt to create a Kingdom of Finland in 1742 is a little known chapter in the history of Finland. Following the Russian occupation in the Russo-Swedish War and vague promises of making the country independent, Finns elected the then Duke Peter of Holstein-Gottorp as the King of Finland...

 of their country to Duke Peter of Holsten-Gottorp

Peter III of Russia

Peter III was Emperor of Russia for six months in 1762. He was very pro-Prussian, which made him an unpopular leader. He was supposedly assassinated as a result of a conspiracy led by his wife, who succeeded him to the throne as Catherine II.-Early life and character:Peter was born in Kiel, in...

, the heir apparent to the Russian Crown.

Another party at the Russian court, represented by pro-Swedish Count Lestocq and Peter's Holsteinian relatives, proposed to return Finland to the Swedes in recompense for having his uncle, Adolf Frederick of Holstein-Gottorp, elected as heir to the throne of Sweden. Empress Elizabeth of Russia lent her support to the latter faction, partly because she fondly remembered Adolf Frederick's brother, her projected spouse who had died several months before the wedding could take place (in June 1727).

According to the resultant treaty, Sweden ceded to Russia

Russian Empire

The Russian Empire was a state that existed from 1721 until the Russian Revolution of 1917. It was the successor to the Tsardom of Russia and the predecessor of the Soviet Union...

 the areas east of the Kymi River

Kymi River

Kymi river is a river in Finland. It begins from the lake Päijänne, flows through the provinces of Päijät-Häme, Uusimaa and Kymenlaakso and discharges into the Gulf of Finland. River passes the towns of Heinola and Kouvola...

 with the fortress of Olavinlinna

Olavinlinna

Olavinlinna is a 15th century three-tower castle located in Savonlinna, Finland. It is the northernmost medieval stone fortress still standing.- Construction :...

 and the towns of Lappeenranta

Lappeenranta

Lappeenranta is a city and municipality that resides on the shore of the lake Saimaa in South-Eastern Finland, about from the Russian border. It belongs to the region of South Karelia. With approximately inhabitants Lappeenranta is the largest city in Finland...

 and Hamina

Hamina

Hamina is a town and a municipality of Finland. It is located in the province of Southern Finland and is part of the Kymenlaakso region. The town has a population of and covers an area of ofwhich is water. The population density is...

. Hence, the Swedish border was moved to the north in accordance with the wishes of Bestuzhev's faction. On the other hand, the Swedes agreed to elect Adolf Frederick as the crown prince. This move exposed the country to the risk of war against Denmark, hence the Baltic Fleet

Baltic Fleet

The Twice Red Banner Baltic Fleet - is the Russian Navy's presence in the Baltic Sea. In previous historical periods, it has been part of the navy of Imperial Russia and later the Soviet Union. The Fleet gained the 'Twice Red Banner' appellation during the Soviet period, indicating two awards of...

 sailed to Stockholm

Stockholm

Stockholm is the capital and the largest city of Sweden and constitutes the most populated urban area in Scandinavia. Stockholm is the most populous city in Sweden, with a population of 851,155 in the municipality , 1.37 million in the urban area , and around 2.1 million in the metropolitan area...

 to protect the Swedish capital in case of Danish attack. The territories were incorporated into the Governorate of Vyborg.

After the treaty, Russia came to control the southern part of Karelia

Karelia

Karelia , the land of the Karelian peoples, is an area in Northern Europe of historical significance for Finland, Russia, and Sweden...

. However, Elizabeth guaranteed religion, properties, laws and privileges of the inhabitants of ceded territories. For example, these territories had just a few years earlier adopted (together with the rest of then-Sweden) the 1734 General Law of Sweden.