GOG Becomes More Awesome

What makes the ultima series good (from 4 and onward) is the setting and philosophical issues the games deal with. Each game tackles its own issues, and each game (after 4 and not including 7 part 1) also questions the validity of the ideals that you are supposed to live by.
7 also has an incredibly well crafted world, with great NPCs and many interesting locations. The worlds really feels alive, far more so than the worlds of most modern CRPGs. The other games in the series are not as good at this (though 8 makes a good effort).

Yeah, it was the philosophical aspect which blew my mind playing Ultima 4 at an early age. That game made me think about things that no other game had up until then. Things that were actually applicable to real life. These days, some games delve into this area, but back then it was unheard of.

Also, the attention to detail in the world-building was very noteworthy in the later Ultimas. Ultima 6 + 7 pioneered levels of object interactivity that hadn't been seen in RPGs prior to that. Like Fnord mentioned - these worlds feel like living, breathing worlds.

The non-linear, open-world exploration aspects are very strong in the Ultima series as well.

Originally Posted by Myrkrel
Also, the attention to detail in the world-building was very noteworthy in the later Ultimas. Ultima 6 + 7 pioneered levels of object interactivity that hadn't been seen in RPGs prior to that. Like Fnord mentioned - these worlds feel like living, breathing worlds.

It wasn't just prior RPGs… most of today's RPGs are badly lacking in interactivity and freedom compared to a game like Ultima 7.