A descent into madness with conquistadors searching fruitlessly for El Dorado, that Werner Herzog dragged a full movie crew down the Amazon to shoot.
In which a king sacrifices basically everything that matters for the sake of his own pride, manifested through giving Indian classical music parties, as you do.
Your reader poll winner is a high-flying martial arts extravaganza that I think was the first subtitled movie I (and lots of other people) saw in a theater.
The story of women trapped and exploited in a gilded cage, the first film by a female director to come out of the Arab World.
The first film from Sub-Saharan Africa to make a big splash in Europe and the US, its story about the toll of colonization is very relevant even today.
A rural village in the Philippines is dragged into the modern world when a local girl claims to see a vision of the Virgin Mary.
A lot more people know the idea of it than have actually seen it, but it really is worth watching.
Maybe the first feature film dealing with themes of homosexuality, it feels surprisingly fresh today.