I was curious if it's possible to download the default wallpapers from the previous Ubuntu versions. I know that I can probably Google them, but I'd rather download them from one of Ubuntu's official sites. Thanks!
You can install wallpapers from past Ubuntu versions (or other Ubuntu flavors) by installing the packages that contain the wallpapers.
sudo apt install ubuntu-wallpapers-raring
sudo apt install ubuntu-wallpapers-natty
You can get the full list by searching in
synaptic (you may need to install it) or from the command line with
apt search wallpapers