Albdag was a Frisian count from the 9th century. Albdag controlled the gouw

Oostergo Eastergoa (also Ostergau, Ostergo, or Oostergo) was one of the Seven Sealands and one of the three ''gau (territory), Gaue'' within what is today the province of Friesland in the Netherlands. Area On its west side Eastergoa was bordered by ...

in Central

Friesland Friesland ( ; ; official ), historically and traditionally known as Frisia (), named after the Frisians, is a Provinces of the Netherlands, province of the Netherlands located in the country's northern part. It is situated west of Groningen (p ...

, which is the part of Friesland between

Vlie The Vlie or Vliestroom () is the seaway between the Dutch islands of Vlieland, to its southwest, and Terschelling, to its northeast. The Vlie was the estuary of the river IJssel in medieval times. Today it's still possible to reach the port of ...

and

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

. Friesland is now a province of the

Netherlands , Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...

He ruled in the name of

Louis the German Louis the German (German language, German: ''Ludwig der Deutsche''; c. 806/810 – 28 August 876), also known as Louis II of Germany (German language, German: ''Ludwig II. von Deutschland''), was the first king of East Francia, and ruled from 8 ...

in the era when the Jutish

Vikings Vikings were seafaring people originally from Scandinavia (present-day Denmark, Norway, and Sweden), who from the late 8th to the late 11th centuries raided, pirated, traded, and settled throughout parts of Europe.Roesdahl, pp. 9� ...

dominated the Netherlands. In 873, the Viking

Rodulf Haraldsson Rodulf Haraldsson (died June 873), sometimes Rudolf, from Old Norse Hróðulfr, was a Viking leader who raided the British Isles, West Francia, Frisia, and Lotharingia in the 860s and 870s. He was a son of Harald the Younger and thus a nephew of ...

made a predatory raid on Oostergo. The people organised themselves with the help of a Christian Norman to resist the invaders. Rodulf was killed in the battle. Herre Halbertsma has argued that the battle would have occurred around the church of

Dokkum Dokkum is a Dutch fortified city in the municipality of Noardeast-Fryslân in the province of Friesland. It has 12,669 inhabitants (February 8, 2020). The fortifications of Dokkum are well preserved and are known as the ''bolwerken'' (bulwarks) ...

References

Annalen van Fulda
Luit van der Tuuk (Gjallar) *, ''Het rijk van de Friese koningen'', (''Realm of the Frisian kings'') (Utrecht, 2000). *{{aut, D. Kalma, ''Skiednis fan Fryslân'', (''History of Friesland'') (Grou, 1965), page 109. (Grevenammen). Counts of Frisia