Reinier Camminga was the ninth potestaat or governor of Friesland

Friesland

Friesland is a province in the north of the Netherlands and part of the ancient region of Frisia.Until the end of 1996, the province bore Friesland as its official name. In 1997 this Dutch name lost its official status to the Frisian Fryslân...

 now a province of the Netherlands

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

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Reijner Haijes Camminga was captain when the Danes made an incursion into Oostergo in 1306 because of disputes with the Frisians.

Occo Scarlensis wrote about a drawn out battle after which the Danes retreated beyond the Lauwers

Lauwers

The Lauwers is a river in the Netherlands. It forms part of the border between the provinces of Friesland and Groningen. From the 730's to Widukind's defeat in 785 it was part of the border of the Frankish Empire....

. This battle would have been against Eric VI of Denmark

Eric VI of Denmark

Eric VI Menved was King of Denmark and a son of Eric V and Agnes of Brandenburg.He became king in 1286 at age 12, when his father was murdered 20 November by unknown assailants...

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