Michigan never formed any thing as large as a brigade. The 14th Michigan Infantry Regiment was sometimes known as the Irish-American Regiment. The Jackson Guard of Detroit was known as an Irish company it joined Mulligan’s Irish Brigade of Chicago. The Shamrock Guard was a Detroit company that apparently did not last too long. The Irish Zouave a.k.a. 1st Zouaves was also a Michigan company formed by Irish citizens. I sure there were other I an not aware of.