Jason Roy and captain Joe Root both smashed centuries as the tourists easily reached their target of 361 with eight balls to spare in Barbados.
It was their highest ever run-chase in the format.
Chris Gayle's innings of 139 off 129 balls went in vain as the Windies' poor form in ODI cricket continued.
The second encounter of the five-match series will be played on Friday.

India spooked by Hazlewood as Australia claim T20 win
Rodrigues-powered India stun Australia to reach World Cup final
Mena Golf Tour confirms 2025–26 schedule
Juventus appoint former Italy manager Spalletti as head coach
Chelsea's Maresca fumes over 'stupid, embarrassing' Delap red card
