So the history is actually really well described in crpgaddicts blog. First there was wizardry (basically all rpgs both in the us and japan are descendents of wizardry, some with the mixture of ultima). bard's tale is a wizardry clone (its wizardry in a city). Dungeon master is an attempt to make a better wizardry, taking advantage of the mouse and the amiga's graphics (its basically wizardry in real time). EotB is a dungeon master clone.

I played Bard's Tale as a kid. Sadly it was a pirated copy and I was missing some of the documentation.

I got stuck because I didn't realize you actually needed a bard to sit on a throne to get past a particular puzzle. Since I never leveled a bard, I never got past that...