At the beginning of the 16th century the political divisions were variable but, since 1503, there were four main slottslen (castle provinces), each with about 30 smaller sub-divisions.
In 1560, they were: They covered the areas of the modern Vestland county (previously Hordaland and Sogn og Fjordane).
Trondheim and North Norway were still parts of the Bergenhus len.
Since then, the number of the len's sub-divisions was gradually reduced as the provincial and national administrations both became more stable.
In 1919, Nordre Bergenhus amt was renamed as Sogn og Fjordane fylke (county) and Søndre Bergenhus amt became Hordaland fylke, and each of their amtmann were retitled as a fylkesmann (country governor).