And the Italian and Eastern European immigrants were heavily discriminated against, though not to the scale of what happened to the Irish that escaped the Great Potato Famine of the 1840's (that group of Irish immigrants couldn't speak English, let alone literate in even Irish Gaelic). Indeed, the very fact one Thomas Edison went after Jewish filmmakers and movie theater operators at beginning of the 20th Century in New York City was why just about every major Hollywood studio founded between 1910 to 1925 were all founded by people of Jewish descent.
But getting back on topic, pizza became popular nationally first. It wasn't until the 1970's that bagels started to become nationally well-known.