Steward's try sent England into the break with a narrow 11-10 leadAustralia (10) 17Try: Wright Con: Lolesio Pen: Lolesio England (11) 21Tries: Steward, Smith Con: Farrell Pens: FarrellEngland held off Australia to seal a series win, with Freddie Steward and Marcus Smith's tries either side of half-time proving decisive.
The tourists started slowly and were 10-3 adrift towards the end of the first half following Tom Wright's try.
But Steward stretched over from short range to snatch the lead before Smith grabbed a loose ball and sprinted in.
Folau Fainga'a burrowed over but England's defence stood firm against late pressure to keep the hosts at bay.
Steward, prop Ellis Genge and scrum-half Jack van Poortvliet, a core from Premiership champions Leicester, leapt in delight as the referee's whistle blew.
It is only England's second series win down under, following 2016's whitewash.
That clean sweep came after a Six Nations Grand Slam and in the midst of a record-equalling winning streak.
This England team is far less settled or strong.
But coach Eddie Jones will hope that a memorable victory at the Sydney Cricket Ground will galvanise his team and propel them towards a testing autumn, featuring meetings with South Africa and New Zealand, and next year's World Cup in France.
England find a way after slow start
Smith scored his fifth England try of the season after an Australian errorJones spoke in the build-up of developing a side that could switch between brain and brawn to find glory at France 2023.
For much of the first half though, the Wallabies posed problems that proved beyond them.
Australia dominated the early territory and, while Owen Farrell's kick put England on the scoreboard first, the hosts were first to cross the whitewash.
Wright broke down the right wing, and excellent support from scrum-half Nic White saw the pair swap quick-fire passes to befuddle the England cover and buy Wright time and space to get in at the corner.
Noah Lolesio's penalty just after the half-hour nudged Australia out into a justified 10-3 lead.
Eddie Jones responded by wielding the knife. Scrum-half Danny Care was withdrawn, replaced by Van Poortvliet.
Whatever that switch signals for Care's international future after his recent recall following four years off the scene, it seemed to spark something in England.
Freeman, a lively, elusive runner, hit a line to put England within inches.
When it was recycled, Van Poortvliet flashed the ball blind for Steward to squirm between two green and gold shirts and score.
Genge, bristling with intent, left Samu Kerevi on the seat of his shorts early in the second half, ruffling Australia and rousing his team-mates.
Farrell slotted the penalty as a backpedalling Australia infringed before Smith's opportunism gave England a clear cushion.
The England fly-half pounced as Australia overshot a line-out, pinching the ball, pirouetting through a tackle and scampering in from long range.
Fainga'a ploughed underneath Farrell to reel England to within four points with 14 minutes left.
Australia threw free-running league convert Suliasi Vunivalu into the fray as they sought to snatch a score and the series, but England quelled their comeback and silenced Sydney Cricket Ground.
'They gave us a bit of fuel'
England captain Courtney Lawes speaking on BBC Radio 5 Live: "We dug in, fair play to Australia with the casualties they have had, they did a great job and put us to the test but we stuck together and stuck at it.
"We fought for each other, we had a great four weeks here and enjoyed it. They gave us a bit of fuel in the press, we stuck to out guns, we found a way to win."
Australia's Michael Hooper: "We created good opportunities tonight, but just not good enough to execute them. There were areas that hurt us, like right before half-time when they got that try. But also some pleasing elements, but it hurts."
Man of the match - Courtney Lawes (England)
Lawes topped England's tackle count with 15 and was a constant turnover nuisance to the WallabiesTeams
Australia: Hodge, Wright, Paisami, Kerevi, Koroibete, Lolesio, White, Valetini, Hooper (capt), Wilson, Philip, Frost, Tupou, Porecki, Slipper.
Replacements: Fainga'a, Bell, Ala'alatoa, Leota, Samu, McDermott, Ikitau, Vunivalu.
England: Steward, Nowell, Porter, Farrell, Freeman, Smith, Care, B Vunipola, Ludlam, Lawes (capt), Hill, Chessum, Stuart, George, Genge.
Replacements: Cowan-Dickie, M Vunipola, Heyes, Isiekwe, Willis, Van Poortvliet, Joseph, Arundell.
