Moeen Ali, centre, celebrates the dismissal of Sri Lanka's Niroshan Dickwella with teammates.
England crushed Sri Lanka by 211 runs with a day to spare in winning a test in Galle for the first time on Friday.
Set an improbable target of 461 and two days to do the unprecedented, Sri Lanka was all out for 250 after tea on the fourth day, Rangana Herath conceding the match in his farewell test trying to get a second run but diving a whisker short.
This earned England it's biggest win against Sri Lanka in terms of runs, eclipsing a 137-run win at Lord's in 1991.
This was also England's first win overseas in more than two years. It had gone 13 tests away from home without a win, losing 10.
"We played some really good stuff. We were consistent throughout the four days," England skipper Joe Root said. "That partnership between Jos (Buttler) and Foakesy (Ben Foakes) was vital after lunch (from 103-5 on day one) and from that point on we were pretty much in control of things. Really pleasing to be in this position going into the second game."
England posed the question of whether Sri Lanka's batsmen possessed the resolve to take the game to the final day, and they fell short badly as spinners Moeen Ali and Jack Leach, playing his third test, shared seven wickets.
Ali finished with 4-71 and a match bag of 8-137.
Sri Lanka coach Chandika Hathurusingha rued missed opportunities, especially on the first day.
"The first day, until lunch we were top of the game having taken five wickets for 100. But after that, the way they batted, they took the game away from us," Hathurusingha said. "In test cricket, especially on wickets like these, it is very difficult to come back.
"First innings, our batting was poor. They outplayed us in all three departments of the game."
England posted 342 and 322 declared. Sri Lanka replied with 203 and 250.
Former captain Angelo Mathews scored the only half-century in the second innings as several top order batsmen fell for loose shots. Mathews was dismissed after tea for 53, caught by Jos Buttler at short mid-wicket off Ali. Mathews scored a half-century in the first innings, too.
There was a glimmer of hope for Sri Lanka as openers Dimuth Karunaratne and Kaushal Silva batted well without any major hiccups in the first hour of the morning. But soon after the morning drinks break, Leach broke through when he had Silva out leg before wicket for 30.
Karunaratne offered a return catch to Ali on 26.
Dhananjaya de Silva was dismissed in the last over before lunch for 21 as Ben Stokes found the outside edge of the bat and the catch was snapped up by Root at first slip.
Sri Lanka lost Kusal Mendis (45) and captain Dinesh Chandimal (1) in the afternoon session. Chandimal, who was nursing a groin strain, could miss the second test at Pallekele next week.
England needed five wickets in the last session to go 1-0 up in the three-test series, and there was not much resistance from Sri Lanka.
Herath walked into a standing ovation, and another when he was the last man out for 5. He retired as the most successful left-arm bowler ever, having taken 433 test wickets to sit in a tie for eighth on the all-time list.
England's players did a lap of honour to the appreciation of more than 6,000 of its fans at the game. England hadn't won four previous tests here.
Ben Foakes, who made a key 107 and 37 on debut as the replacement wicketkeeper, was named the man of the match.
"Test cricket is grinding. It's hard work," Foakes said.
"It won't sink in until afterwards when I speak to family and stuff. It all happens so quickly. The big thing for me is just making my debut, being able to say you're an England test cricketer. Regardless of what's happened, that's such a special feeling that no-one can take away."
England won the ODI series 3-0 and the one-off Twenty20.
