Savonlinna or Nyslott lies in the south-east of Finland. Here, the Castle of Olofsborg was built in 1475 in order to give protection the growing population of the Savolax region. Erik Axelsson Tott owned the castle. Next to the castle, the town of Savonlinna was established. The Russians said that the castle was built on Russian ground and occupied it in 1495-1496.
During the great Nordic war, the castle was attacked and given up to the Russians in 1712. It was returned to Sweden at the peace of Nystad in 1721. In 1742, the castle surrendered again. At the peace of Åbo in 1743, the castle and the town of Savonlinna became Russian.
Savonlinna was granted a Swedish town charter between 1639 and 1683 and recieved a Russian town charter in 1784. In 1812 the town was reunited with Finland, then a Russian principality.
Nowadays, the best known cultural event of Finland, "The Opera Festival in Nyslott, takes places at Olofsborg in July every year.