---
title: "Pre-Columbian transoceanic contact theories"
chunk: 8/11
source: "https://en.wikipedia.org/wiki/Pre-Columbian_transoceanic_contact_theories"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:37:53.813777+00:00"
instance: "kb-cron"
---

Some have conjectured that Columbus was able to persuade the Catholic Monarchs of Castile and Aragon to support his planned voyage only because they were aware of some recent earlier voyage across the Atlantic. Some suggest that Columbus himself visited Canada or Greenland before 1492, because, according to Bartolomé de las Casas, he wrote he had sailed 100 leagues past an island that he called Thule in 1477. Whether Columbus actually did this and what island he visited, if any, is uncertain. Columbus is thought to have visited Bristol in 1476. Bristol was also the port from which John Cabot sailed in 1497, crewed mostly by Bristol sailors. In a letter of late 1497 or early 1498, the English merchant John Day wrote to Columbus about Cabot's discoveries, saying that land found by Cabot was "discovered in the past by the men from Bristol who found 'Brasil' as your lordship knows". There may be records of expeditions from Bristol to find the "isle of Brazil" in 1480 and 1481. Trade between Bristol and Iceland is well documented from the mid-15th century.
Gonzalo Fernández de Oviedo y Valdés records several such legends in his Historia general de las Indias of 1526, which includes biographical information on Columbus. He discusses the then-current story of a Spanish caravel that was swept off its course while on its way to England, and wound up in a foreign land populated by naked tribesmen. The crew gathered supplies and made its way back to Europe, but the trip took several months and the captain and most of the men died before reaching land. The caravel's ship pilot, a man called Alonso Sánchez, and a few others made it to Portugal, but all were very ill. Columbus was a good friend of the pilot, and took him to be treated in his own house, and the pilot described the land they had seen and marked it on a map before dying. People in Oviedo's time knew this story in several versions, though Oviedo himself regarded it as a myth.
In 1925, Soren Larsen wrote a book claiming that a joint Danish-Portuguese expedition landed in Newfoundland or Labrador in 1473 and again in 1476. Larsen claimed that Didrik Pining and Hans Pothorst served as captains, while João Vaz Corte-Real and the possibly mythical John Scolvus served as navigators, accompanied by Álvaro Martins. Nothing beyond circumstantial evidence has been found to support Larsen's claims.
The historical record shows that Basque fishermen were present in Newfoundland and Labrador from at least 1517 onward (therefore predating all recorded European settlements in the region except those of the Norse). The Basques' fishing expeditions led to significant trade and cultural exchanges with Native Americans. A fringe theory suggests that Basque sailors first arrived in North America prior to Columbus' voyages to the New World (some sources suggest the late 14th century as a tentative date) but kept the destination a secret in order to avoid competition over the fishing resources of the North American coasts. There is no historical or archaeological evidence to support this claim.

=== Irish and Welsh legends ===

The legend of Saint Brendan, an Irish monk from what is now County Kerry, involves a fantastical journey into the Atlantic Ocean in search of Paradise in the 6th century. Since the discovery of the New World, various authors have tried to link the Brendan legend with an early discovery of America. In 1977, the voyage was successfully recreated by Tim Severin using a replica of an ancient Irish currach.
According to a British myth, Madoc was a prince from Wales who explored the Americas as early as 1170. While most scholars consider this legend to be untrue, it was used to bolster British claims in the Americas vis-à-vis those of Spain.
The "Madoc story" remained popular in later centuries, and a later development asserted that Madoc's voyagers had intermarried with local Native Americans, and that their Welsh-speaking descendants still live somewhere in the United States. These "Welsh Indians" were credited with the construction of a number of landmarks throughout the Midwestern United States, and a number of white travelers were inspired to go look for them. The "Madoc story" has been the subject of much speculation in the context of possible pre-Columbian trans-oceanic contact. No conclusive archaeological proof of such a man or his voyages has been found in the New or Old World; however, speculation abounds connecting him with certain sites, such as Devil's Backbone, located on the Ohio River at Fourteen Mile Creek near Louisville, Kentucky.
At Fort Mountain State Park in Georgia, a plaque formerly mentioned a 19th-century interpretation of the ancient stone wall that gives the site its name. The plaque repeated a claim by Tennessee governor John Sevier that Cherokees believed "a people called Welsh" had built a fort on the mountain long ago to repel Indian attacks. The plaque has been changed, leaving no reference to Madoc or the Welsh.
Biologist and controversial amateur epigrapher Barry Fell claims that Irish Ogham writing has been found carved into stones in the Virginias. Linguist David H. Kelley has criticized some of Fell's work but nonetheless argued that genuine Celtic Ogham inscriptions have in fact been discovered in America. However, others have raised serious doubts about these claims.

== Claims of transoceanic travel originating in the New World ==

=== Claims of Egyptian coca and tobacco ===