Short answers, pulled from the story.
The word celery was first printed in English as "sellery" by John Evelyn in 1664. It derives from the French céleri, which came from the Italian seleri, tracing back to the Latin selinon, borrowed from ancient Greek. The earliest attested form is the Mycenaean Greek se-ri-no, written in Linear B script.
Celery was a chthonian symbol in ancient Greece, associated with death and the underworld. Celery leaves were used as garlands for the dead. Winners at the Isthmian Games and the Nemean Games were crowned with celery wreaths before those traditions changed to pine and other materials.
Yes. Researchers Daniel Zohary and Maria Hopf identified celery leaves and inflorescences among the garlands recovered from the tomb of pharaoh Tutankhamun, who died in 1323 BCE. Celery specimens dated to the seventh century BCE have also been recovered at the Heraion of Samos.
According to the New York Public Library's historical menu archive, celery was the third-most-popular dish listed on New York City menus during the 19th and early 20th centuries, ranked behind only coffee and tea. It was served in celery vases, salted and eaten raw.
The three main cultivar groups are stalk celery (Dulce Group), grown for its edible fibrous petioles; leaf celery (Secalinum Group), grown for its aromatic leaves; and celeriac (Rapaceum Group), grown for its large edible hypocotyl. All three were selectively bred from the wild species Apium graveolens.
Yes. For people with a celery allergy, exposure can cause potentially fatal anaphylactic shock. Apium graveolens has an OPALS allergy scale rating of 4 out of 10. In the European Union and the United Kingdom, foods containing celery, even in trace amounts, must be clearly labeled by law.