It is located approximately 145 km (90 mi) east of the country's capital Helsinki, in the Kymenlaakso region, and formerly the province of Southern Finland.

[8] As the commercially vibrant city of Vyborg was lost to Russia in 1721, Fredrikshamn (named in 1723 in the honor of King Frederick I of Sweden) was dedicated to replace it.

The star-shaped fortress and the circular town plan, designed by Axel Löwen, were based on Central European and Italian Renaissance concepts from the 16th century.

[10] In 1743, Hamina was surrendered to Russia, after the Russo–Swedish War, 1741–1743, and the town of Loviisa was the next Swedish candidate for an Eastern-Finnish trade center.

The Treaty of Fredrikshamn (1809), by which Sweden ceded Finland, including parts of the province of Lappland and Åland, was signed in Hamina.

Thus Sweden was split, and the eastern half was formed into the Grand Duchy of Finland, an autonomous part of the Russian Empire.