There is a theory about anti-Semitism without Jews. Looney, I know, but you can probably google some articles on it.
This guy was the leader of the Hungarian Soviet Republic which lasted from 1919 to 1920 when communists took over Hungary
What's Bela got to do with Hungarian anti-semitism? well, his father was of Jewish origin (and his mother was a former Calvinist) -- no one cared that he was educated at the Calvinist college etc., but they care that his original surname was Kohen
The revolution's leaders were all, except for one of Jewish ancestry -- Bela Kun, Tibor Szamuely, Jeno Landler -- key note: ancestry
The presence of these people identified as Jews (though in reality they were part or less of Jewish origin and none were practising, leave alone believing Jews) was a reason to create the notion of a Jewish-Bolshevik conspiracy (note that it was the same in Russia where Trostsky was of Jewish origin as was 15% of the Bolshevik party)
They also have the historical grievance of the fall of Budapest when Ibrahim Pasha, the vizier of Suleiman came to Buda, the city Jews (who were the only ones left in the city) came and begged for grace and handed the keys of the castle -- yes, this was a token gesture as the castle was already deserted, but it's still noted as "the ... gave the keys of Budapest to the Turks"
note though that the "White" leader Admiral Horthy refused to send Hungarian Jews to German death camps until the Germans occupied Hungary
Note also that there were large numbers of people of Jewish origin in the communist government of Matyas Rakosi (1948-1954), further exacerbating the myth of the Jewish-Bolshevik link
People would also need to note that the head of the secret police, Peter Gabor and the Premier Gero had jewish backgrounds yet had anti-semitic sentiments
So, this background of associating Jews with the evils of communism has fuelled modern-day anti-semitism in Hungary