I knew someone would answer Dragon Lord. That was the trap. Actually, the original Dragon Warrior villain is the Archfiend Zoma.

Dragon Warrior 1 takes place after Dragon Warrior 3. In Dragon Warrior 3, Erdrick must go on a quest to stop the Archfiend Zoma while the world of Alefgard is still a world of darkness. It isn't until Dragon Warrior 1 happens years later that Alefgard becomes a world of light. Dragon Lord appears and takes Zoma's old castle, Charlock, for himself. From that point on, Dragon Warrior 1 happens, followed by Dragon Warrior 2.

But you were pretty close, so I guess you ask a question now.