Shalom and thank you for your question! You ask if Passover was ever banned by the nations?
I am not expert in Jewish history, however what I have encountered is that Passover per se, as a Jewish holiday, was not specifically banned by the nations, however it became fertile ground for the infamous blood libels that occurred repeatedly throughout Jewish history, from ancient times until very recent times. If I am not mistaken, in early twentieth century Hungary, there was a blood libel, but it was proved to be false, as also happened repeatedly. Poor mobs in Europe and in North African countries would be incited by their local minister or religious leader, or a prominent anti-semite, and they would plant a bottle of blood in a Jewish synagogue or the home of a Jewish leader, and then bring the police, followed by a blood-thirsty mob, to see the ‘evidence’ of the Jews having murdered a non-Jew (usually a child who had gone missing,) in order to use his blood for preparing their Matzot, the special unleavened bread used on Passover. In many cases the mob had their way and a pogrom ensued, and in other cases miracles happened, and the Jews were proven to be innocent. I recall a story where the supposedly ‘murdered’ young person actually turned up in the courthouse alive and well, thank G-d.
Jews are forbidden by the Torah, the source of Jewish law, to consume the blood even of a kosher animal. After the process of kosher slaughtering, which is quick and painless due to an especially sharp slaughtering knife which is repeatedly checked for sharpness and any nicks or imperfections which might cause suffering to the animal, G-d forbid, there is a koshering process whereby blood is drained and rinsed and also the meat undergoes salting and rinsing, so that as much blood as possible is actually removed from the meat or fowl. Therefore the accusation that Jews would use human blood was always a ludicrous one.
In the context of general Jewish history, there were several periods where keeping many of the commandments in the Torah was forbidden to the Jews, for example by the Greeks and the Romans when they conquered Israel centuries ago. Notably the commandments that were forbidden were commandments such as circumcision, keeping the laws of the Sabbath, announcing the new moon monthly, and more. In the former Soviet union under the rule of Stalin, Jews were forbidden to educate the younger generation regarding anything to do with Judaism, and were effectively prevented from keeping Judaism, for although the communists professed to provide freedom of religion, they hounded anyone who propogated Judaism, allowing only elderly people to attend synagogues, installing spies to listen to what the Rabbis were saying at the pulpit, and imprisoning, torturing, killing and exiling to Siberia people who dared to to teach Jewish children in underground schools.
Despite all this, there were famous Chassidic Jews who sanctified the name of G-d by continuing against all odds to keep the flame of Judaism alight, and somehow even the communist government sometimes did not stand in the way of certain righteous people, such as Rabbi Levi Yitzhak Shneerson, the father of the Lubavitcher Rebbe, who received their permission to oversee the manufacture of kosher Matzot for Pesach! (Rabbi Shneerson was later arrested for the ‘crime’ of keeping up Judaism in general, and exiled to Siberia, where he became weak and ill and passed away, but he had left a legacy of self-sacrifice, and Torah teachings which he wrote even in the intense poverty and difficult conditions of his exile.)
We pray and hope for the time when, by virtue of the Jews keeping the 613 commandments of the Torah, and the non-Jews keeping the Seven Noahide laws, (which include setting up courts of justice, not committing murder or adultery, and not eating part of a live animal, amongst others,) there will be no question of religious freedom, for ‘Nation shall not lift sword against nation,’ and everyone will live in peace and harmony, and ‘the knowledge of the L-rd shall cover the earth as water covers the sea.’