Just over four years ago, the Black Cats were languishing in League One - the third tier of English football.
But they won promotion to the Championship in 2022 and climbed into the Premier League via the play-offs in May 2025, finishing a surprise seventh in their first season back in the big time.
The northeast club have a storied history - only six clubs have more top-flight English titles - but the sixth and last of those came way back in 1936.
Sunderland were a byword for glamour in the 1950s, dubbed the "Bank of England club" due to their heavy spending.
But they had relatively little to show for their outlay, and last won a major trophy in 1973, when they beat Leeds in the FA Cup final.
Despite their prolonged stagnation, the club, about 12 miles from bitter rivals Newcastle, remained one of the best supported in England, attracting crowds of 30,000-plus even in League One.
Now the 49,000-capacity Stadium of Light, opened in 1997, is staging Premier League football again and preparing to host continental football for the first time.
The European journey is rich reward for Kyril Louis-Dreyfus, son of the late Marseille owner and billionaire Robert Louis-Dreyfus, who bought a stake in the club in 2021 and has since increased his shareholding.
The appointment of Regis Le Bris as head coach in June 2024 proved a masterstroke - the Frenchman took the club back into the Premier League at the first attempt and they defied the odds last season.
Sunderland, led by inspirational captain Granit Xhaka, are now gearing up to face AZ Alkmaar after a patchy start to their season.
"It's a symbol for the club. We are getting better, the momentum is big and for our fans it is going be crazy to be fair," Le Bris told TNT Sports.
"We are really proud to be in this position. We earned this opportunity last season with a great season. We had tough moments but at the end we stayed consistent."
He added: "It's important to show our desire, to show the city, our togetherness, the connection with our fans."
Sunderland joy
For fans of Sunderland, the journey in recent years has been dizzying.
"Supporting Sunderland has gone from being a solemn duty, which you used to curse the misfortune of your postcode and/or your parents for, to something that, for the first time in generations, is bringing joy to people's lives," Michael Lough wrote on the Wise Men Say website.
"Usually, the higher up the pyramid you go, the hollower and more soulless the experience becomes, and the wider the disconnect between the fans and the players grows.
"Regis Le Bris likes to use the word 'connected' in his press conferences, and I can't remember the last time the city, the players, the fans and the club felt this level of connection."
Joining Sunderland in the Europa League this season are Bournemouth, who are playing continental football for the first time in their history.
Andoni Iraola led the southcoast club to a sixth-place finish last season but then left for the Liverpool hot seat, meaning Marco Rose will be in charge.
Bournemouth, who travel to Spain to face Real Sociedad on Thursday, are yet to win in the Premier League this season despite leading in all four games after developing a frustrating habit of conceding late goals.
"Everyone here in Bournemouth is looking forward to this game," said German coach Rose. "It's going to be a special night for the club against top opposition. I'm really proud to be part of this."
A third English club, Crystal Palace, are in the Europa League courtesy of winning the UEFA Conference League last season.
Premier League clubs have dominated the competition in recent seasons thanks to their vast resources with Aston Villa and Tottenham winning the Europa League in the past two seasons.
But the more unheralded trio of English clubs this time could balance the playing field up against some of Europe's biggest clubs such as AC Milan, Juventus and Benfica.