Is it possible to run Leopard on late 2011 Macbook Pro Not asking about Snow Leopard but Leopard. Have install disc.
Trying to figure out how to install on partition.
Currently Mac is running High Sierra on main drive.
Need this to run some software.
General rule is no Mac can run an OS older than itself. There are no drivers for hardware that wasn't yet invented. The 2011 Macbook Pro runs OS X 10.7.2 at minimum.
You could normally run an older OS in a VM, but Leopard isn't licensed for virtualisation (see What are the technical and license restrictions around virtualization for Leopard, Snow Leopard and Lion?).