Tyrker (or Tyrkir) is a character mentioned in the Norse Saga of the Greenlanders and German historical legend He accompanied Leif on his voyage of discovery around the year 1000, and is portrayed as an older German male servant. He is referred to as “foster father” by Leif Ericson, which may indicate he was a freed thrall, who once had the responsibility of looking after and rearing the young Leif.
Leif and his company wintered in the New World after building Leifsbudir (Leif’s dwellings), perhaps somewhere in Newfoundland or the adjacent area. According to the saga, he divided his men into two parties, which took turns in exploring the neighborhood. He cautioned his followers to keep together and return to sleep at their quarters. One evening Tyrker did not return with his party. Greatly distraught, Leif, at the head of twelve men, went in search of him, and he had not gone far when he discovered the old German, greatly excited, gesticulating wildly, and evidently drunk. “Why, my fosterer,” cried Leif, “have you come so late? What made you leave your companions!” Tyrker answered in German, but when remembering that the Norsemen could not understand him, he spoke, after some time, in their tongue: “I have not gone very far; still I have some news for you. I have discovered vines loaded with grapes.” “Are you telling the truth, my foster-father?” exclaimed Leif. “I am sure of telling the truth,” Tyrker said, “for in my native land there are vines in plenty.” This caused Leif to give the country the name of Vinland.
The story shares the element of wild grapes with the Irish tale of Mael Duin. However, the Norse word used in the saga is ‘vinber’. While this sometimes refers to grapes, it also translates into "wine-berry", and there is a long-standing Nordic tradition to make wine out of berries available. We know from historical records that the Icelanders and Greenlanders even made wine from crowberry. In the Newfoundland/Labrador area, squashberry, gooseberry, and cranberry all grow wild, and may serve as an explanations for Leif’s discovery of "wine-berries".
- Wilson, James Grant; Fiske, John, eds. (1889). "Tyrker". Appletons' Cyclopædia of American Biography. New York: D. Appleton. which in turn cites:
- Adam of Bremen, Historia Ecclesiastica
-  "The German explorer and discoverer Tyrker reached a continent now called North America in the year 1000."