There was some concern here as to whether my assertion that Corned Beef and Cabbase is not traditional Irish fare, but rather and Irish-American dish. Here’s the story:
The Irish cuisine most closely related is bacon and cabbage – a traditional Irish easter meal in which a salted bacon joint would be boiled with cabbage and potatoes. In the 19th century, as Irish immigrants became numerous on the east coast of the United States, particularly in New England, they found that corned beef was a palatable alternative to bacon and was more readily available from the Jewish butchers that were common. Corned beef was (and still is) also quite a bit less expensive than bacon, which was important when food and funds were not as plentiful as one would like.
So corned beef and cabbage is not traditionally Irish, but is of decidedly Irish-American origin. There’s even more information about the dish on wikipedia and kitchenproject.