Conversation so far:
What did Juan Ponce de León have to do with spain?
Juan Ponce de León was born in the village of Santervás de Campos in the northern part of what is now the Spanish province of Valladolid
Who were Juan Ponce de León's parents?
The identity of his parents is still unknown, but he appears to have been a member of a distinguished and influential noble family.

Question: what was his greatest accomplishment?
Self-contained rewrite: What was Juan Ponce de León's greatest accomplishment?