Britain's Roger Hammond made history after taking third place on the third leg of cycling's World Cup in France.
Backstedt was a surprise winner of the famous race
Hammond, who rides for the Mr Bookmaker team, claimed the best finish of any British rider since Barry Hoban's third in the early 1970's.
Alessio rider Magnus Backstedt of Sweden outsprinted Dutchman Tristan Hoffman of CSC to finish first.
Backstedt's winning time in the "queen of the classics", was six hours, 46 minutes and 12 seconds.
There were numerous attacks and crashes during the race, which was first run back in 1896.
Hammond said he felt his chance came after he looked in three-time winner Johan Museeuw's eyes after the Belgian had attacked on the ninth-last cobblestone section.
"I saw Museeuw attack on section nine and I so I attacked him myself and looked in his eyes and thought 'okay, I think he knows I'm here today', so I attacked again," added Hammond.
"So on that sector I thought, 'yeah I'm in Paris-Roubaix today', although I overcooked it a bit on sector nine then sector six I really had a hard time. After that I got my feet back on the ground and so I thought I just had to start looking after myself."
The winner could barely contain his own emotion after victory.
"It's the biggest day of my life. I've got tears in my eyes and I just can't believe it," said Backstedt.
"I just tried to stay at the front the whole day, stay out of trouble and away from the wind."
1 Magnus Backstedt (Swe) 6 hours 46 minutes 12 seconds
3 Roger Hammond (GB)
4 Fabian Cancellara (Swi)
5 Johan Museeuw (Bel)
6 Peter van Petegem (Bel)
7 Leon van Bon (Ned)
8 George Hincapie (US)
9 Tom Boonen (Bel)
10 Frank Hoj (Den)
World Cup standings (after three of 10 rounds)
1 Steffen Wesemann (Ger)
2 Oscar Freire Gomez (Spa) 103
3 Magnus Backstedt (Swe)
4 Leif Hoste (Bel) 84
5 Tristan Hoffman (Ned)
6 Erik Zabel (Ger) 70
7 Leon Van Bon (Ned)
8 Peter Van Petegem (Bel) 58
9 George Hincapie (US)
10 Erik Dekker (Ned) 51