The flag of the former county of Vestfold, Norway. Its design is shared with the county arms, and shows a mediaeval style royal crown, representing Vestfold's special connection to Norway's oldest royal dynasty. Harald Fairhair, from which Norwegian kings in the following centuries claimed to have descended, belonged to the Yngling dynasty, which ruled Vestfold when it was its own kingdom in the 9th century.  The flag was approved by royal resolution 1970‐01‐30.
Vestfold fylke, flagg – Arkivverkets digitale fotoarkivForskrift om fylkesvåpen og fylkesflagg, Vestfold – Lovdata
Oldest file version was based on File:..Vestfold Flag(NORWAY).png
Hallvard Trætteberg, vectorization by VulpesVulpes42
Oldest file version created by Gunnar Offel