Short answers, pulled from the story.
The Swedish Viking Age lasted roughly from the eighth century to the 11th century. Swedish Vikings and Gutar mainly travelled east and south going to Finland Estonia the Baltic countries Russia Belarus Ukraine the Black Sea and even as far as Baghdad.
Gustav Vasa became king on the 6th of June 1523 marking what is sometimes considered the foundation of modern Sweden. This date is now celebrated as Sweden's National Day and the monarchy became hereditary in 1544 after Gustav Vasa broke the monopoly power of the Hanseatic League.
In 1709 the decisive Russian victory at the Battle of Poltava marked the beginning of the end for the Swedish Empire. As the war finally ended in 1721 Sweden had lost an estimated 200,000 men and was forced to cede large areas of land in the Treaty of Nystad in 1721.
Sweden joined the European Union on the 1st of January 1995 after a referendum passed with 52.3% in favour on the 13th of November 1994. The country developed its industrialized economy between 1870 and 1914 before joining the union.
The highest point in Sweden is Kebnekaise at 2,096 meters above sea level while the lowest elevation is in the bay of Lake Hammarsjön near Kristianstad at 2.41 meters below sea level. At 450,295 square kilometers it is the fifth-largest country in Europe and the largest country in Northern Europe.