They were driven from the Iberian Peninsula in one of Europe's notorious purges. But more than 500 years after the last Jews and Muslims were "ethnically cleansed" from Spain and Portugal, their ancestors are thriving.

Spanish film starlet Penelope Cruz or the Oscar-winning director Pedro Almodovar might originally be descended from Jewish stock. Equally, the tempestuous Portuguese football manager Jose Mourinho or the Nobel prize-winning novelist Jose Saramago may well have had Muslim ancestors.

These intriguing genealogical possibilities arose after a study found evidence that 19.8 percent of today's Spaniards and Portuguese have Sephardic Jewish ancestry. Another 10.6 percent have a genetic make-up that suggests they were descended from North African Moors.

The study found that the genetic signatures of Spaniards and the Portuguese indicate evidence of mass conversions of Sephardic Jews and Muslims to Catholicism from the 15th century.

In 1492 King Ferdinand II of Aragon and Queen Isabella I of Castile completed the Reconquista (Recapturing) of the Iberian Peninsula by Catholic forces from the Muslim rulers who had held what is today Spain and Portugal since 711.

The Catholic monarchs then forced Jews and Muslims to convert to Catholicism or go into exile. Despite their best efforts to "ethnically cleanse" the Iberian peninsula, the genetic fingerprint of Jews and Muslims remains until today.

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