Silver medallists at Beijing 2008, the USA finally won gold as they held off a challenge from Russia, while Romania claimed the bronze medal.
Defending champions China were left distraught as they finished fourth by some margin.
The United States began on the Vault, with world champion McKayla Maroney the pick of the team after she hit a stunning stuck Amanar vault to score 16.233.
That gave the USA a huge early lead, and from that point they never looked back.
Russia did stay in touch to make a competition of it and they fought valiantly to claw back the deficit, but Aly Raisman's world-class Floor routine was enough to seal the victory for the USA and send them to the top step of the podium.
I would hope that we will be able to inspire a generation. I know that we all had role models. We all sacrificed a lot, but it's been worth it to become gold medallistsJordyn Wieber
Jordyn Wieber, 2011 world all-around champion, admitted she remained focused on what her team had to do rather than casting a glance at the opposition during the high-pressure final.
'We didn't pay much attention to the scores. We went to each event and we were confident', Wieber said.
'This is the most important competition. I'm proud of every single person on this team, we all did our job.
'I would hope that we will be able to inspire a generation. I know that we all had role models. We all sacrificed a lot, but it's been worth it to become gold medallists.
'I really did just go out there and made the most of my Olympics, and I'm happy I ended on this note.'