RichThesaurus
get someone's Irish up
vs
get someone's back up
get someone's Irish up
verb
To anger or annoy someone.
get someone's back up
verb
To annoy or anger someone.
That joke really got my boss's back up.
How often have the words
get someone's Irish up
and
get someone's back up
occurred in a corpus of books?
(source:
Google Ngram Viewer
)