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The De Castro family is a Sephardi Jewish family of Portuguese-Jewish origin. Soon after the establishment of the Portuguese Inquisition, members of the family emigrated to Bordeaux, Bayonne, Hamburg, and various cities in The Netherlands. Their descendants were later to be found scattered throughout The Netherlands, Turkey, Egypt, Germany, Italy, the United Kingdom and the United States.
Some branches of the family have continued to bear the simple name of "De Castro", others are known by De Castro-Osorio, De Castro Sarmento, De Castro-Castello-Osorio, Pereira de Castro, De Castro Vieira de Pinto, Rodriguez de Castro, Orobio de Castro, De Castro de Paz, Henriquez de Castro, etc. The name often appears as "de Crasto". Notice that Castro is not in origin a Jewish but an Iberian Christian name, adopted by Portuguese and Spanish Jews after the forced conversions of the late 15th and early 16th centuries.