Although many people believe Christopher Columbus was the first European to discover North America, historians claim there is evidence that indicates the Vikings explored the continent 500 years before Columbus. Historians and archeologists have generated different theories about the Vikings’ presence in North America since 1960, when archeologists found evidence of Viking pieces and house foundations in Newfoundland, Canada. Archeologists have also been searching for artifacts of Native American tribes in Newfoundland. Historians are puzzled by references to Vineland in the ancient document Sagas of Icelanders, so they are researching which parts of North America were referred to as Vineland. If the underlined sentence were deleted, the paragraph would primarily lose a detail that .

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