Sir Bobby Charlton scored twice that night, once to break the deadlock and give United the lead early in the second half, and once in extra-time to win the cup for his team.
George Best, who finished 1968 with a Ballon d'Or to his name, and Brian Kidd added further goals in the additional 30 minutes as United won 4-1 to take their place as Kings of Europe.
Exactly half a century later, Charlton has today tweeted, "I have always felt privileged to be part of the Manchester United family. But no more so than fifty years ago today, when as captain of the greatest football club in the world, I lifted the European Cup on behalf of my fellow players, coaches, and supporters."
I have always felt privileged to be part of the @ManUtd family. But no more so than fifty years ago today, when as captain of the greatest football club in the world, I lifted the European Cup on behalf of my fellow players, coaches, and supporters. pic.twitter.com/QKPQ5rrz4g— Sir Bobby Charlton (@SirBobby) May 29, 2018
Benfica had twice won the European Cup earlier in the 1960s under the management of esteemed Hungarian coach Bela Guttmann. They were the first team other than Real Madrid to win it after five consecutive trophies made their way to the Spanish capital in the earliest years of the competition and boasted the quite incredible Eusebio among their ranks.
Eusebio had the chance to win the 1968 final for Benfica, but was denied by a now iconic close range save by United goalkeeper Alex Stepney, which the Portuguese striker openly applauded his opponent for, such was his humble and sporting nature.
United of course had their own stars. A teenage Best had destroyed Benfica in Lisbon in March 1966. That same year, Charlton won the World Cup and received the Ballon d'Or. Denis Law, who was forced to miss the 1968 final with injury, had also won the Ballon d'Or in 1964.
It was United's 1966/67 First Division title that had qualified them for the European Cup. In the first round, they disposed of Maltese champions Hibernians, followed by closer ties against Sarajevo of Yugoslavia and Gornik Zabrze of Poland in the second and third rounds respectively.
In the semi final, United edged out six-time champions Real Madrid. Best scored the only goal of the first leg at Old Trafford, before a 3-3 draw in the Bernabeu, sealed with goals from Sadler and Foulkes, handed the English champions a narrow aggregate win.
ON THIS DAY: In 1968, Manchester United beat Benfica 4-1 to win the European Cup for the first time in the club’s history. pic.twitter.com/4Ftm5pSQRn— ManUtd Fact (@ManUtd_Fact) May 29, 2018
Benfica, meanwhile, had cruised past Juventus in the other semi and the two would meet at Wembley. Benfica had played there before, losing the 1963 final to AC Milan, but it was the first time that United, or indeed any English club, had made it so far.
When United triumphed it was about more than just winning the European Cup and making in history. For manager Sir Matt Busby it was vindication and the completion of the club's rise from the ashes of the Munich Air Disaster just over 10 years earlier.
Busby was a pioneer when it came to English clubs playing in Europe. As reigning champions of England, Chelsea had been invited to play in the first ever European Cup in 1955/56, but were persuaded to drop out after pressure from the FA and Football League.
Busby famously ignored such voices at home and sent United into continental action. His team reached the semi finals of the competition in 1957, only losing to eventual champions Real Madrid. United also made it to the last four the following year after prevailing in the quarter finals against Red Star Belgrade, before meeting tragedy on the way home to Manchester.
Heroes of 1968 - Sir Bobby Charlton— Full Time DEVILS (@FullTimeDEVILS) May 29, 2018
Skippered Manchester United to a European Cup win 10 years after the Munich Air Disaster bagging a brace in the final - just one chapter in the remarkable story of Sir Bobby! #MUFC #OnThisDay pic.twitter.com/sHQ1s5mtci
Duncan Edwards, Roger Byrne, Tommy Taylor, Eddie Colman, Mark Jones, Liam Whelan, David Pegg and Geoff Bent were the eight United players who lost their lives as a result of the Munich Air Disaster when the plane carrying the team failed to take off after a refuelling stop in the German city and crashed off the end of the runway.
Busby himself was badly injured and was close to death more than once. He pulled through, but was initially reluctant to remain in football after what had happened. Ultimately, the great man was persuaded to continue because the players who died wouldn't have wanted him to give up.
And so, 10 years on from Munich, Busby had succeeded. United, the first English club to enter the European Cup were the first English club to be crowned European champions.
Today is the 50th anniversary of 1968 European cup victory over Benfica at Wembley.— Totally Man Utd™ (@TotallyMUFC) May 29, 2018
Back row: Nobby Stiles, Pat Crerand, S. Brennan, Alex Stepney, Bobby Charlton and Bill Foulkes. Front row: Tony Dunne, Brian Kidd, David Sadler, George Best and John Aston#mufc pic.twitter.com/CwAXt3jDL5
Busby later remarked: "The moment Bobby took the cup, it cleansed me. It eased the pain of the guilt of going into Europe. It was my justification."
Charlton himself said: "