Ha, home has been traditionally always on a separate drive. That's the reason why root user has the home under /root and not /home/root, so that it can login even if the home drive didn't Mount.
As a curiosity, even /usr was traditionally on a separate drive and that's why critical binaries and libraries where under /bin and /lib while all non critical stuff under /usr. It is called "split-usr".
Nowadays /usr is always on the same drive as root, and we moved to a "merge-usr" approach where stuff under /lib and /bin is a symlink into /usr/lib and /usr/bin.
Because when HDDs where 50mb in size, even that small binary file counted as big :)