Our comrades over at The Red Nation have some videos on Hawaii that might be helpful, and there's also another video from Rob Kajiwara, an Okinawan comrade whom also covers Hawaii and Okinawa.
I suppose about the coup itself, ways American hegemony was forced onto the Hawaiian people (forced cultural assimilation, schooling, and what not), how American rule harms the natives to this day. I have a vague sense of what happened, but nothing really concrete.