National celebrations in calendar order:

National Korean Day (January) 

Korean American Day (January)

French Language Day (March)

National Foreign Language Week (March)

6 Ways to Celebrate National Foreign Language Week (March)

Greek Heritage Month (March)

National Indigenous Languages Day (March 31)

National Arab Heritage Month (April)

National Bilingual/Multilingual Learner Advocacy Month (April)

National ASL Day (April 15)

Jewish American Heritage Month (May)

Asian Pacific American Heritage Month (May)

Russian Heritage Month (June)

National Hispanic Heritage Month (September)

National Teach German Day (October)

National Italian Heritage Month (October)

National French Week (November)

National American Indian Heritage Month (November)