The Hammers won their first major trophy since the 1980 FA Cup, and a first European title since 1965, when they beat Italian side Fiorentina 2-1 in Prague on Wednesday night.
And their jubilant supporters, decked out in the famous claret and blue on a warm and sunny evening in the capital, packed the pavements as the Hammers paraded the silverware on an open-top bus.
The squad’s journey started at the site of their former home at Upton Park and finished at Stratford Town Hall, where they enjoyed a reception.
Only West Ham fans of a certain age will ever have seen their side celebrate success like this, with a similar parade being held after that 1965 European Cup Winners’ Cup victory, where the likes of Bobby Moore, Geoff Hurst and Martin Peters got the taste of winning trophies.
But the younger generation made the most of it, climbing on lamp posts and bus stops to get the best vantage point of their heroes while also letting off flares.
David Moyes may have joined Ron Greenwood and John Lyall in earning immortality as managers to win a major trophy with the Hammers but he initially endured a lessened role on the bus, taking pictures of his players as they posed together.
But he was soon joining in with the celebrations, dancing and jigging with the trophy on his head.
Lifting the trophy appears to be a fitting way for captain Declan Rice to bow out, with chairman David Sullivan confirming the England international will be allowed to leave the club this summer, with a bidding war expected to commence soon.
Rice was emotional on top of the bus, admitting it does not feel “real”.
“This is absolutely incredible, when you’re a kid and you love football as much as I do, and the lads do, you see teams having trophy parades,” he said. “I was once a kid watching teams do trophy parades and now to be doing one and captaining the side is just so, so special, I can’t even put into words.
“We knew it would be exciting and the fans would come out, I am just trying to take it all in, we don’t get to experience this ever. These moments don’t come around very often.
“I’ve seen top captains over the years lift trophies and it was my time at West Ham to lift the trophy. It doesn’t really feel real.
“At 24, captain of West Ham lifting a trophy in a European competition, I don’t think it is going to hit me for a while, but I am going to enjoy it and be as happy for as long as possible.
“Bobby Moore, Billy Bonds, I am seeing messages that I am now in that category, I don’t really know what to say. Bizarre.”
Moyes spent much of the season under pressure following a disappointing Premier League campaign, but Rice believes he is now the club’s best-ever manager.
The England midfielder added on Sky Sports News: “I think he goes down as the best manager West Ham have ever had. The circumstances, when he first came in, kept us twice, European competition, we finished fifth, sixth, a semi-final (Europa League) and now we’ve won this, he deserves all the credit he gets.
“He’s a top man and as you can see he is buzzing.”
Jarrod Bowen was West Ham’s hero in the final as he scored a 90th-minute winner, capping off a remarkable turnaround in his career having been playing at non-league Hereford nine years ago after being rejected as a youngster by Aston Villa.
“I love the game and these moments make it all worth it, the rejections and not going the way you want it,” he said.
“You fast forward 10 years and you are on an open-top bus parade for winning a European trophy so from where I have come, my mum was crying on the phone, my dad was there.
“It is a bit surreal to say I have won a European trophy from where I have come from. I love it.”