Lyric discussion by Whodini24 

Cover art for Harmony Hall lyrics by Vampire Weekend

"We took a vow in summertime Now we find ourselves in late December I believe that New Year's Eve Will be the perfect time For their great surrender

To me, this is someone thinking about a planned revolution of sorts. He's reflecting on when the plans for this revolution were first hatched (in summertime, either literally or metaphorically) and how the time has come to implement their plan and face the harsh reality of it (in the cold hard months of winter) which will coincide with the dawning of the new year (a revolution of it's own) The lyrics suggest that their is an internal conflict here: Ideology vs practical reality.

But they don't remember Anger wants a voice Voices wanna sing Singers harmonize Till they can't hear anything Thought that I was free From all that questioning But every time a problem ends Another one begins

Seems to me that he's suggesting that those ideologues that truly wanto see their revolution come about fail to remember that people are not inherently ideological. Although "anger wants a voice", what most voices want to do is sing, and not disturb the degree of harmony that exists, regardless of whether or not it fits the ideology. The person describing these things is still tied to the ideology and those involved, but he'd rather just be free of their rules and inquisitions as to whether or not he's been operating for the cause of the revolution.

And the stone walls of Harmony Hall bear witness Anybody with a worried mind can never forgive the sight Of wicked snakes inside a place you thought was dignified I don't wanna live like this, but I don't wanna die (Ooh ooh ooh ooh) I don't wanna live like this, but I don't wanna die

This suggests that the Government and/or Universities have become a breeding ground for ideologues. These are institutions that were built by ethical people that knew the value of morality and education and the places that used to place the highest value upon challenging and rigorous debate, have become a den for vipers. Ideologically-driven professors, politicians and bureaucrats have debased the esteem of places of higher learning and the sanctity of self-reflective government.

Within the halls of power lies A nervous heart that beats Like a Young Pretender's Beneath these velvet gloves I hide The shameful crooked hands Of a money lender 'Cause I still remember

This suggests that he is a man in a position of power, but he hasn't earned that position in the same way that the generations that came before him did. He is a pretender to the throne, disguising his truly wicked and debased nature with softly-spoken words and political correctness. He is a puppet-master that cannot expose his true self because that would cause disillusionment in the view of the people that he is manipulating to his agenda.

My Interpretation

@Whodini24 where in the world do you get all of that in relation to this song and the writer of it?. It seems to me that you are projecting some of your personal beliefs onto this song. The song makes no mention of politics let alone revolution. The vow taken could be personal instead of political and the song does not make this clear. I could assume that the wicked snake is Donald Trump and the other snakes are his supporters. whether or not it seems to be supported by the text a case could be made.But alas I too...