there were jewish settlements in the iberian peninsula during roman times which predate christianity. during the time of muslim rule jews nostly used their own hebrew names and they spoke ladino, the language spoken by spanish and portuguese sephardic jews. after the expulsion jews were forced to leave spain and portugal or they had to convert to catholicism. some jews sincerely converted while others refused to do so. some practiced their faith in secret eg crypto jews.
at that time jews had to take spanish or portuguese names that were used by old christians. they also took spanish place names and were allowed to take royal names. but they were all spanish or portuguese to begin with. it was at this time that many new christians and cryto-jews left the iberian peninsula and spread into the middle east north africa and persia and all of latin america, esp northern mexico.