The vessel has been called the world's best example of a 15th Century ship by archaeologists.
And new evidence has found that the timbers from the ship have been matched to projects built in the Basque region.
It includes new data from medieval buildings in the Araba and Navarra areas of Spain.
"The mystery of the origins of the Newport Ship, the remains of the a remarkably well-preserved medieval ship may at last have been solved," said Nigel Nayling, associate professor at University of Wales Trinity Saint David.
"Artefacts found at the time of the discovery hinted at Iberian connections but recent advances in dendrochronology (tree-ring dating) have provided the first scientific evidence.
"The results strongly suggest that the ship was originally built in the Basque Country where wooden shipbuilding has a long tradition.
'Useful insight'
"A Basque origin for the ship has been suspected for some time and collaboration between the scientists was first suggested in 2006 by Xabier Agote, president of the Albaola Society which promotes research into Basque maritime heritage."
Mr Nayling said initial attempts to date the ship were unsuccessful.
But he added the latest results have come from research programmes sampling both the ship itself and more historic buildings that have allowed extension and improvement of the medieval section of the Basque chronology.
Debbie Wilcox, cabinet member for leisure and culture at Newport City Council said: "The ship provides an excellent opportunity to tell the story of medieval Newport and its history as an international maritime town long before its development as an industrial port.
"The latest information about the Newport Ship provides a useful insight into its origins and it appears that one of the mysteries of its history may have been solved."
Newport council has put a tender out to developers asking them to recommend a suitable location for the vessel.
It is seeking a specialist company who would be able to provide a new museum based around the ship's history.
A medieval ship discovered on the banks of the River Usk in Newport in 2002 may have come from the Basque country in Spain.