Being a child of the 60s, when it came time to do American history in school, it was right around the time that the bicentennial hype was getting into full swing. The movie 1776 came out right in the middle of that, and of course we watched it in class. It seemed at the time like everyone else saw it, too, and it's been a basic part of my cultural background ever since.
It's a musical treatment of the wrangling leading up to the signing of the Declaration of Independence. The history isn't far wrong, it's loaded with quotable lines, the acting is superb, and it's a fun time all around. Performances by William Daniels as John Adams, Howard da Silva as Ben Franklin, and Ken Howard (in his first major role) as Thomas Jefferson stand out to the point that they've indelibly stamped themselves on my mental images of the people in history.
The runtime in theaters was 2:22, growing to 2:48 on the director's cut DVD and a full three hours on the laserdisc (which is the one disc not in my parents' collection that I wish I had). There's a lot of story to tell, and they manage to keep the suspense going even though we all know damned well what the outcome will be. That it kept a classroom full of eighth graders watching for that long is a testament to just how entertaining it is.
Here's the song "But, Mr. Adams", the one that contains the reference I mentioned:
I was pleasantly surprised to see that the stage musical had been revived a few years back, with Brent Spiner as Adams. That must have been something to see. In any case, it's definitely worth watching, in any form. I hope it doesn't become something that just us old farts remember and enjoy.