Wikipedia remains impressive and it outlasts its critics:
The Basque-Icelandic pidgin was a pidgin spoken in Iceland in the 17th century. It developed due to the contact that Basque traders had with the Icelandic locals, probably in VestfirÃ°ir. The vocabulary was heavily based upon the Labourdin Basque language, but also in an Atlantic pidgin with Romance and English influences.
It is documented in two glossaries found around 1905 by Jón Helgason in the ArnamagnÃ¦an Collection of the University of Copenhagen: Vocabula gallica ("French words") and Vocabula biŠ¿caÃ¯ca ("Biscayne words"). Helgason brought them to the attention of Christianus Cornelius Uhlenbeck, a versatile linguist from the University of Leyden
with an expertise in Basque. His post-graduate student, N.G.H. Deen,
traveled in 1927 to the Basque Country to collaborate with Julio de
Urquijo on the research that Deen published as his doctorate thesis in
1937. The manuscripts were sent back to Iceland in 1986, but one of
them was lost.
I thank darling Yana for the pointer. It almost sounds like something from a Borges story…