The Thirty Years' War (1618–48) involved extensive contact between the Old Swiss Confederacy and the Kingdom of Sweden, which was involved in the war, culminating in Sweden's ten-year occupation of the Fricktal region.
In 1815, Sweden signed the Final Act of the Congress of Vienna, recognising Switzerland's permanent neutrality.
Switzerland dispatched its first consular representative to Oslo in 1847. Until the first Swiss consulate was established in Stockholm in 1887, the Swiss consul residing in Oslo was also responsible for Sweden. From 1867, Sweden maintained a consulate in Geneva, establishing a permanent diplomatic mission in 1915. Switzerland opened a legation in Stockholm in 1919.
King Carl XVI Gustav and Queen Silvia of Sweden made a state visit to Switzerland in 1985. In 2021, President of the Swiss Confederation Guy Parmelin visited Sweden and met King Carl XVI Gustav in Stockholm.
Sweden, Historical Dictionary of Switzerland (fr)
Diplomatic Documents of Switzerland, Dodis (fr, de, it)