Fans were elated, shouting through the rooftops and excited at what this could bring to the city of Leicester in the name of sport.
A late Tigers drop goal was needed to separate the two sides in what was a fast-paced and frenetic encounter.
Saracens took an early lead, but it was the Tigers who put on all the pressure.
Tries from Hanro Liebenberg and Jasper Wiese gave first blood to the Tigers, but a series of penalty kicks from Owen Farrell slowly brought Saracens back level with just four minutes to go.
Step up substitute Freddie Burns, who buried a drop goal with just minutes remaining to secure victory and the Tigers first title since 2013.
Going into the semi-finals Leicester had finished top of the league on 94 points, with Saracens not far behind in second place on 87 points.
Both teams had overcome difficult opposition in their respective semi-finals.
Leicester came from behind to beat Northampton Saints 27 - 14 and Saracens had taken a 34 - 17 victory against Harlequins.
In a blaze of fire and fireworks the match got underway at 3pm and Saracens immediately pushed the Tigers back, probing their defensive line.
Saracens took the lead on four minutes when a late tackle by Hanro Liebenberg led to a penalty kick. Captain Owen Farrell converted to make it 3-0 to the North London outfit.
Both teams continued to search for territory in the opening ten minutes as each tried to get a foothold in the game.
Leicester were awarded a scrum deep into the Saracen half, just yards away from the try line, but it came to nothing when Dan Cole and Ellis Genge were penalised.
With 21 minutes gone, the Tigers won their first penalty, but George Ford was unable to covert it, putting it wide of the posts.
Another blow for the Tigers came on 24 minutes when Ford had to be substituted.
But that didn't hold the Tigers back for long, as Liebenberg broke through the Saracen defence on 27 minutes to score the Tigers' first try.
And with Burns converting, it made the score 7-3 to the Tigers.
But almost immediately Saracens were handed another penalty, with Elliot Daly scoring to make it 7-6 to the Tigers.
Leicester were in the ascendancy though and they continued to push the Saracens back.
Jasper Wiese scored their second try on 35 minutes as he twisted and turned round the Saracens defences.
Burns couldn't convert this time, but with the scores at 12-6, the Tigers were stamping their authority on the match as they went in for half time.
Saracens came out strong again in the second half as they looked to tighten their grip on the match. They were awarded a second penalty kick but it was a tough one being more than 40 yards out.
Burns was unable to convert, but Tigers continued to attack and push for the win.
The Tigers continued to turn the screws on their opponents dominating the possession as they looked to get a third try.
Tigers fans were in loud voice as they pushed their team forward. Every inch of ground gained was greeted by cheers and applause.
As the half wore on, Saracens desperately tried to get back into the game, trying to find a way through the Tigers' line.
On 64 minutes, Owen Farrell brings Saracen closer to the Tigers when he scores a penalty kick to make it 12-9.
With ten minutes to go, the tension began to build around Twickenham. Tigers fans were hoping their team could hold on and Saracens were hoping for a late breakthrough.
Gasps echoed around the stadium on 74 minutes as Saracens broke through the first line of the Tigers' defence and raced for the try line, but they are halted in their tracks.
This led to a scrum just inches away from the try line but the Tigers give away a penalty.
Farrell once again coverts to make it all square on 76 minutes.
Tension built around the ground and as Leicester pushed for the win, Burns buried a drop goal to make it 15-12 and secure victory for the Tigers.
LEICESTER TIGERS: Freddie Stewart 15, Chris Ashton 14, Matias Moroni 13 (Matt Scott 58 minutes , Guy Porter 12, Harry Potter 11, George Ford 10 (Freddie Burns 22, 26 minutes), Richard Wigglesworth 9 (Ben Youngs 64 minutes), Ellis Genge (c) 1, Julian Montoya 2 (Charlie Clare 64 minutes), Dan Cole 3 (Joe Heyes 58 minutes), Ollie Chessum 4, Calum Green 5 (Harry Wells 64 minutes), Hanro Liebenberg 6, Tommy Reffell 7, Jasper Wiese 8.
SARACENS: Ales Goode 15, Max Malins 14, Elliot Daly 13, Nick Tompkins 12, Sean Maitland 11 (Alex Lozowski 41 minutes), Owen Farrell (c) 10, Aled Davies 9, Mako Vunipola 1, Jamie George 2, Vincent Gough 3, Maro Itoje 4, Nick Isiekwe 5, Theo McFarland 6 (Andy Christie 59 minutes), Ben Earl 7, Billy Vunipola 8.