The Irishman produced a one-over-par round of 72 to finish 15-under for the tournament, with Tommy Fleewood finishing runner-up.
It also banished bad memories from 2016 at the US Open when he squandered a four-shot lead heading into the final round, eventually finishing in a tie for second.
And a stunned Lowry admitted he had an “out-of-body experience” as he struggled to contain his excitement at the prospect of winning throughout a soaked Sunday afternoon at the Dunluce Links, paying tribute to the 237,750 fans who attended this week.
“What can I say? I just have so many people to thank, to have an Open Championship here in Ireland is amazing,” Lowry remarked. “I love this place, it’s one of my favourite places in Ireland. My family, my Mum and Dad. I’m so happy I can hand them this trophy tonight. My wife and little girl, to have them here is extra special. The volunteers and all the fans, this one is for you!
“I feel like I’m in an out-of-body experience, I was so calm, what a day! The weather was so hard, I wasn’t going great, but I saw everybody else struggling.
“It was a two-horse race, which was good for me. I tried to stay focused on staying ahead of Tommy.
“I didn’t, I suppose I talked to Paul, I can’t stop thinking about winning, holding par. He just said, ‘stay with me’, all day, what a job he did today.
I can’t wait to wake up tomorrow morning and feel what that’s like then. I can’t describe what it was like, the next tournament I’ll play will probably feel boring, I’ve never seen something like this on a golf course, they kept me going.”