The National Film Board of Canada is Canada's twelve-time Academy Award-winning public film producer and distributor.
It seems to have had a period in the 60's-80's when it created beautiful short animations. It has an English language and a French language arm, so I'll focus on the French language ones, this being Culturethèque, but I recommend you get sucked into a youtube hole of watching animation after animation.
They have a website, where theoretically, you should be able to watch films for free, but they take a long time to load, so I recommend you go straight to Youtube.
Videos below. This is the ONF's suitably retro logo:
For animations on vimeo, have a look at this blog.