You were on a crew with Thorvald, Leif Erikson's brother, exploring the lands around Vinland and Markland. While sailing down a wide, island studded river, a storm quickly forms and smashes the boat against the shore.
It is summer, and the Christians amongst the group are celebrating the 1000th year of Christ's birth. Leif's colony is hundreds of miles away through unexplored land, assuming it is not a series of islands. Your tools are what were brought on the voyage, your food is what you can hunt or gather, and your world is foreign.