population about 400
The Treaty of Uusikaupunki, preceded by the Great Wrath in 1714–1721, was signed. At the start of the Great Wrath, the Russians attacked deep into Finland; the country was occupied from 1714–1721. Oulu was a piece of "no-man's land" between the warring Russians and Swedes. It was frequently demolished and robbed by Cossack units.
The City of Oulu and Oulu Castle were burned down in 1715. When the war ended, about 40% of all farms in Oulu were deserted. The enemy killed civilians and took the best labourers as prisoners to be used for forced labour in Russia. The population dwindled.
population about 400
The flooding River Oulujoki discharged itself into the open sea so forcefully that it formed the Toppila Inlet. This sheltered inlet was an ideal place for a harbour, and the harbour created there soon became the most important seaport in Oulu. The old and shallow Hahtiperä Port near the marketplace continued to operate as an inland port to which goods were brought from Toppila and the roadstead.
population about 1,000
"We do not hesitate to assert that our people cannot be beaten by anyone for their honourable life and noble mind." Quotation from a doctoral thesis by Johannes Snellman, approved in 1737 at the University of Turku.
population about 1,400
Oulu received foreign trade rights. It was now free to carry out foreign trade; however, foreign ships were not allowed into Oulu. The most important export goods were tar, timber, salmon and butter. The most significant import goods were salt, tobacco, alcohol, sugar and goods from the colonies (fruit, coffee, tea and cocoa).
population about 2,400
Oulu became the capital of Oulu Province and the home of the governor. Lieutenant Colonel Karl Magnus Jägerhorn was appointed as the first governor of Oulu Province.
Pharmacist Johan Julin became the first person in the Nordic countries to fly a hot air balloon – only a year after the Montgolfier brothers Joseph and Étienne, who were the first in the world to do so.
population about 3,400
Giuseppe Acerbi, an Italian explorer, travelled around the Nordic countries and also visited Oulu, which was at the time the second biggest city in Finland by population, the biggest being the capital, Turku. Acerbi got to know several people in Oulu, including the county treasurer, Erik Tulindberg, who was a musical master (violin, cello) and a ground-breaking Finnish "art music" composer. Acerbi (clarinet) and Tulindberg (cello) formed a quartet with other local players and entertained the Oulu gentry on several occasions with chamber music.