It doesn't matter if your Polish or Italian or African American. If you live in Illinois, you get to celebrate Casimir Pulaski Day on March 5th every year (since 1978)!
This little known holiday is one that Illinois and a few other places with considerable Polish populations (and Polish elected officials, to be exact) share. So have a kielbasa and maybe a perogi or two and be merry!!
More about Casimir Pulaski Day (link)