A slottslän (Finnish: linnalääni) was a type of secular[note 1] administrative division throughout the Kingdom of Sweden from late 13th century to 1634.
Although the word "län" literally means fief, in Sweden it is translated as "county" and in Finland as "province".
There also existed län which were granted to noblemen for their services to the King.
[1] Slottsläns were established by Birger Jarl to replace the lething system in the latter-half of the 13th century.
[2] Slottsläns were disbanded in 1634 following Axel Oxenstierna's land reform and replaced with provinces.