O’Sullivan – forced to wear trainers all week due to an ankle injury – thrashed Kyren Wilson 9-2 in a one-sided final to clinch the £70,000 top prize.
The 41-year-old boasted a breathtaking 98 per cent pot success to be crowned champion and set-up the chance to pocket an unprecedented £1m bonus if he can win all four Home Nations events.
Asked about the £1m bonus – if he can triumph in Northern Ireland, Scotland and Wales this season – O’Sullivan added: “Listen, it is another 21 matches and it is do-able. Anything is possible but over these short matches that are best-of-seven frames, it will be very tough.”
It was O’Sullivan’s first ranking title for 20 months – since winning the Welsh Open in 2016 – although he won a record seventh Masters in January.
But Sunday night’s victory moved him level with John Higgins, on 29, on the all-time list of ranking title wins. Only Stephen Hendry has won more trophies in snooker history.
It was fitting that the English Open final was contested by two Englishman, at the end of a week when players from Iran, India, Switzerland and China have pushed snooker’s global boundaries to the limit.
“It is great to win another ranking title,” said O’Sullivan. “I am my own worst critic at times but it was very, very good today.
“I made a lot of good and important breaks, and felt good among the balls. I will keep driving myself on to reach a higher level.
“I am enjoying the challenge of hanging in there against these young players, but you play well if you have to – and I know what a good player Kyren is.
“The foot is ok, I suppose I have to give some credit to the trainers I have been wearing all week!”
O’Sullivan – who beat Anthony McGill 6-4 in Saturday’s semi-final – went into Sunday night’s evening session with a 6-2 advantage.
It was an afternoon of vintage Ronnie, with two centuries and four other breaks of 50-plus.
When the Chigwell potter is smashing in big breaks, like his 115 in the opening frame, and a 131 to make it 3-1, his opponent must grab any chance.
A pivotal moment came at 1-1, which Wilson failed to take advantage of.
After knocking in a confidence-boosting 74 to restore parity in frame two, the Kettering cueman had a glorious chance to edge in front.
The world No 15 potted a superb long pink, before opting to try a thin cut on the black – when playing safe was probably the best option – to leave the ball hanging over the pocket.
It was a match brimming with quality. O’Sullivan downed his tenth century of the week, before Wilson – whose only previous ranking title came at the 2015 Shanghai Masters – responded with a 109 clearance.
But from 3-2, O’Sullivan – competing in his 43rd ranking final – showed his ruthless side, reeling off the next three frames in 27 minutes with breaks of 77, 87 and 96.
Wilson had reached the final by ending the amazing run of Swiss rookie Alexander Ursenbacher, with a 6-3 semi-final win on Saturday.
The 21-year-old – Switzerland’s only professional snooker player – only regained his place on the tour in March after winning the European Under-21 title.
But Wilson never threatened a comeback in Sunday night’s resumption.
At 6-2, O’Sullivan came to the table, trailing in the frame and with the balls in tricky positions, but produced a sublime 50 clearance before finishing with back-to-back centuries of 127 and 132. That made it 12 centuries in Barnsley for O’Sullivan who edged back up the world rankings from 12th to 9th.
Wilson said: “I feel like I made it too comfortable for Ronnie at times. He obviously put me right under pressure, he played out of his skin today. To hold that level of concentration throughout the whole day was very impressive.
“Ronnie was a hero of mine growing up.
“I didn’t feel like I was completely out of the match after the first session.”