The Great Schism represents the break between the Eastern and Western churches. I know that a primary bone of contention that the East had with the West was Rome's insistence on Papal Supremacy. My understanding is that for a millennium there had been an understanding that Rome would be first among equals, and clearly this somehow fell apart.

I'd like to know

what was the proximate cause of the mutual anathema,

why they each anathematized the other (one would assume that one side could have denounced the other, but mutual allegations seem odd), and

why a simple governance question couldn't be resolved politically.

And, finally, for bonus points :) I understand that the Pope recently (like in the 1990s) has reconciled with the Orthodox. Is this true, and how did it come about?

Note: There is already a question about filioque so feel free to gloss over any details about that in particular. Per cwallenpoole, it is a fairly contentious thing.

Put another way, Can't we all just get along?