|This doesn't end well.|
However, it being Polski Piątek, I will bring your attention to an Italian-born Polish queen named Bona Sforza. She is often credited with Italian influences upon Polish cuisine. She is also blamed for the death of her daughter-in-law, the beautiful Barbara Radziwiłł, and was apparently herself poisoned---possibly by an agent of Philip II of Spain. As Philip was the devoutly Catholic king consort of Mary I of England, this rumour is eye-opening. Really, Wikipedia is dangerous--you click on one thing, and then you click on another, and then it is noon already.
According to this, Queen Bona was disgusted by 16th century meat-heavy Polish feasting habits and ordered her own court to adopt a sort of Nouvelle Cuisine--less food on the plate, but more expensive, better quality and including vegetables. (NB Meat-consumption was, as usual, for the rich. According to Wiki, the medieval Polish poor subsisted mainly on grains--like kasza--and beans.)
The Italian queen had oranges, lemons, pomegranates, olives, almonds, broccoli and cauliflowers imported from Italy. The article says, however, that Italian recipes weren't widespread in Poland for another two hundred years. Meanwhile, long before Bona got to Poland, the sons of rich Polish families travelled to Italy to be educated, so it is likely they brought back at least "a stick of celery." (Wiki claims King Jagiello had plenty of vegetables at his court 80 years before Bona turned up.)
Apparently Bona hired Italian chefs, so continued eating Italian food through her married life. Meanwhile, I have wasted much time reading Wiki's list of regional Polish dishes, defeating the purpose of my Polish to Italian mental crossover. Here is an article about Umbrian cooking instead.