This name change occurred when a family of a knight was raised to the title of Baron.
Åke Axelsson (1594-1652)
He was a privy councillor, Marshall of the Land, and Marshall of the Realm. Ake was descended from Nils Sigridsson, a knight. He, his nephew, and his nephew’s son were raised into the titles of Baron in 1652 by Queen Christina.
Åke Natt och Dag (1652-1655)
This periphrastic surname would continue and there is a site dedicated to the House members.
- (Image Attribution) Sundin, Christer. “COA family se Natt och Dag.” Wikipedia. 16 March 2009. CC BY-SA 3.0.
- “Natt och Dag.” Wikipedia.
- “Natt Och Dag: Hemsidan”. Natt och Dag.org.