I lived there for 3 years from Jan 1991 - Jan 1994, and had a lot of Arab friends and workmates, so I've got a superficial (although probably out-of-date) idea. read more
The Shia are the majority, but the Sunni are in generally more privileged positions - the Royal family, positions in the BDF (Bahrain Defence Force - the Army and Police rolled into one), appointed to positions in the Ministries, etc. read more