SOULE is the French name of ZUBEROA, the smaller basque region, but the richer in culture and traditions, The main Town of Zuberoa is MAULE. I think this surname was originated for one man born on Zuberoa, that lived in France (or served in the French army), and as his surname was difficult for the french people, they begin to call him SOULE, because of his origin. Of course is a very personal Theory.

The people of Zuberoa are called Zuberotarrak, in Spanish Suletinos, and in French Souletins. The people of Zuberoa pronounce Zuberoa (SHIBEROO)