Having worked for seven years on the certification process of the descendants of Sephardic Jews of Portuguese origin the Rabbinate of the Jewish Community of Porto (CIP/CJP) emphasises that the overwhelming majority of the certificates issued so far by CIP/CJP were granted to applicants descending from traditional Sephardic families who for centuries lived in Balkan countries – Macedonia, Greece, Bulgaria and the former Yugoslavia – and in Arab or Muslim countries – Turkey, Lebanon, Syria, the former Palestine, Morocco, Algeria, Egypt, Tunisia and Libya – where marriages between Jews of Portuguese origin and Jews of Spanish origin were common for many generations.

"There are now some two million Sephardic Jews of Portuguese and Spanish origin living outside the Iberian Peninsula in various parts of the world. The majority of these live in the State of Israel." - Edmond Malka, The Jews from Iberian Peninsula, 1977, pag. 158.
During the fourteenth and fifteenth centuries, before the Edict of Expulsion of 1492 and 1496, the Jewish families of Portugal and Spain were the same because of marriages and permanent trade relations. Abulafia, Aragones, Zekri, Baruc, Barzilai, Benatar, Calderon, Dayan, Franco, Funes, Gabay, Galego, Habib, Hadida, Harari, Nahmias, Sarfati, Sevilhano, Shalom, Sofer, Toledano, Veniste, Verdugo, Vivas, Zacuto, and others were common surnames.

Although in international literature Sepharad (Iberian Peninsula) was and continues to be confused with “Spain” (as if Portugal had always been a region of Castile), there are two major branches of Jews in the world: the Ashkenazi branch (originating in central and eastern Europe) and the Portuguese branch. This is a very true affirmation, and indeed present in the 19th and 20th century literature. "From an ethnic point of view, two species of Jews are ordinarily distinguished: those of the Portuguese branch and those of the German branch (Sephardim and Ashkenazim).” - Kadmi Kohen in Nomades, 1929, page 129.

It was from Portugal (a veritable Judea in the late 15th century with about 200 thousand souls integrated in a total population of under 1 million inhabitants) that the Jews departed to found, on the one hand, the modern communities of the west (London, Bordeaux, Hamburg, Amsterdam, USA, etc.) and, on the other, together with the Spanish to whom they had always been united in marriage, the traditional Sephardic communities of Africa (Morocco, Algeria, Tunisia, Libya, Egypt, etc.) and the (rest of the) Ottoman Empire (Balkans, Turkey, Syria, Palestine, etc.).

On the other hand, in 1496, at the time of the Edict of Expulsion in Portugal, the Jews in Portugal also included tens of thousands of Spanish Jews (who arrived after the Spanish Edict of 1492) and their destinations were also similar. To that extent, the first large Sephardic communities in North Africa and throughout the Ottoman Empire were in fact the first "Portuguese&Spanish communities."

A Sephardic Jew from a traditional family of North Africa or of the Ottoman Empire will most assuredly have 15th century Portuguese and Spanish ancestors, as five centuries are equivalent to 18 or 19 generations and to approximately half a million ancestors who always intermarried within the Jewish community. This origin cannot be denied.

Portuguese Jews created many "Kahal Kadosh" Portugal, Évora, Lisbon, etc., a Purim Sebastiano (in this case in Morocco where they escaped the new forced conversion) and even languages that mixed Portuguese, Spanish and local dialects (ladino) in which the word for hat is “chapéu” (not “sombrero”), now is “agora” (not “ahora”), and many words that testify to the Portuguese influence.

This is also present in dozens of "New Christians" surnames (Mendes, Pereira, Galante, Nunes, Ventura, Silva, Pinto...) that in the 20th century can be found in all Sephardic communities in the world, from the Balkans to North Africa and to Palestine.

Portuguese influence was such that it actually penetrated into the Ashkenazi communities. Chabad Lubavitch was founded in Rua de Portugal (Portugal Street).

In 2021, a protocol of friendship and cooperation was established between the Historical Society of the Independence of Portugal and the Jewish Community of Oporto. The Protocol evokes the participation of Jewish communities in the formation and development of the Nation" and "the symbolism of the closeness and friendship that was established between King Afonso Henriques (the first king of Portugal) and Yahia Ben Yaish who would become the first Chief Rabbi of the country, held high positions in the administration of the Kingdom and even fought alongside and in the service of the King. The two institutions undertook to hold Annual Meetings, rotating between Lisbon and Oporto,  to address a topic of public relevance and common interest.