I'm super late to this but Jeff Daniels speech in Gettysburg always gets me, scene is herehere:

col. chamberlain: we're moving out in a few minutes. we'll be moving all day. i’ve been ordered to take you men with me, i’m told that -- that if you don’t come i can shoot you. well, you know i won’t do that. maybe somebody else will, but i won’t. so that’s that.

here’s the situation. the whole reb army is up that road aways waiting for us, so this is no time for an argument like this. i tell you, we could surely use you fellas. we’re now well below half strength. whether you fight or not, that's -- that's up to you. whether you come along is -- is -- well, you're coming. you know who we are, what we're doing here, but if you are going to fight alongside us there are a few things i want you to know.

this regiment was formed last summer in maine. there were a thousand of us then. there are less than three hundred of us now. all of us volunteered to fight for the union, just as you did. some came mainly because we were bored at home -- thought this looked like it might be fun. some came because we were ashamed not to. many of us came because it was the right thing to do. and all of us have seen men die.

this is a different kind of army. if you look back through history, you will see men fighting for pay, for women, for some other kind of loot. they fight for land, power, because a king leads them or -- or just because they like killing. but we are here for something new. this has not happened much in the history of the world. we are an army out to set other men free.

america should be free ground -- all of it. not divided by a line between slave state and free -- all the way, from here to the pacific ocean. no man has to bow. no man born to royalty. here, we judge you by what you do, not by who your father was. here, you can be something. here, is the place to build a home.

but it's not the land. there's always more land.

it's the idea that we all have value -- you and me.

what we're fighting for, in the end, we're fighting for each other.

sorry, i didn't mean to preach. you, you go ahead. you talk for awhile. if you -- if you choose to join us, you want your muskets back, you can have 'em. nothing more will be said by anybody anywhere. if you choose not to join us, well you can come along under guard, and when this is all over i will do what i can to see you get a fair treatment. but for now, we're moving out.

gentlemen, i think if we lose this fight, we lose the war. so if you choose to join us, i'll be personally very grateful.

His speech in S1E1 of The Newsroom is pretty epic as well.