Prior to their meeting on Centre Court, Halep had won one of 10 meetings with the American, at the WTA Finals in Singapore five years ago, but she was simply scintillating in swatting aside her rival 6-2 6-2 in less than an hour on this occasion.
In doing so, Halep claimed her maiden title at the All England Club while Williams was left to reflect on a third successive defeat in Major finals.
Halep, meanwhile, now has a second crown to add to the French Open she won in 2018, having lost all three of her grand slam finals before that Roland Garros triumph.
"Well, I thought about the match, but I didn't think at all against who I play," Halep said.
"I [have] always been intimidated a little bit when I faced Serena. She's an inspiration for everyone and the model for everyone.
"Today I decided before the match that I'm going to focus on myself and on the final of a grand slam, not on her. That's why I was able to play my best, to be relaxed, and to be able to be positive and confident against her.
"I decided this morning how I have to play against her. I knew exactly what I have to do to put her in trouble, not letting her make her game.
"When she has time, she plays unbelievable. I played many times against her. I knew how the ball is coming. I knew what she doesn't like that much.
"Today I just went for it like in Singapore. I had that image in my head. I really believed there is the chance to do the same thing. I knew I have to stay there every ball. Otherwise, when she comes back, she's very powerful.
"It's never easy to face a grand slam final. You can get intimidated by the moment. You can get nervous, too nervous.
"I have learned that it's a normal match, not thinking that much about the trophy, just going there and try to be the best as you can. So I did that.
"I said that every time I would play a final of a grand slam, I will do exactly the same thing. So today I did it."