The Swiss, who beat Nadal in the 2014 Australian Open final, was dismantled 6-2 6-3 6-1 on Sunday as Nadal won his 10th Roland Garros title.
Unseeded Jelena Ostapenko of Latvia used bold strokes and an unbending will to come back and stun No. 3 Simona Halep 4-6, 6-4, 6-3 in an enthralling French Open final Saturday for the first title of her career.
Key Stat: Nadal ended Federer's 27-match winning streak at majors, preventing him from a fourth Grand Slam title in a row.
On a fifth break point at 3-2 the Spaniard gratefully received a simple netted backhand to move ahead and then he clinched the set at 5-2 with a forehand long from his opponent.
"He's the best ever on clay; it's always a tough challenge".
An emotional Rafael Nadal described his 10th French Open title as the flawless end to a ideal fortnight after he made history at Roland Garros on Sunday. After years of nagging injuries, Nadal continued his dominance on clay courts - the Spaniard is 79-2 in his French Open career, and 102-2 on clay courts overall. "This is the most important event of my career".
"It was hard", said Nadal's uncle and coach, Toni.
Nadal had played down La Decima.
A year ago an emotional Nadal withdrew from the French Open due to injury, but 12 months later the imperious left-hander dropped to his favourite red surface with his head in his hands before clutching the Coupe des Mousquetaires like a newborn baby.
Nadal's withering surge - brutal and clinical - not only wounded unsafe Wawrinka, it obliterated the Swiss.
Former top-ranked Andy Roddick has expressed his astonishment at Rafael Nadal's incredible run to his 10th French Open title.
"I played against the biggest clay-court player ever", Wawrinka said.
No other man or woman has won 10 championships at the same major in the Open era.
Nadal is no longer the 19-year-old who won the French Open in his debut in 2005, wearing long white pirate shorts, his flowing locks wrapped by a white headband, his sleeveless shirt revealing bulging biceps. The nerves, the adrenaline I feel when I play on this court, it is impossible to compare.
The sun is shining, there is barely a trace of cloud in the sky and the temperature is about 85 degrees (30 Celsius) as Sunday's title match approaches.
Nadal was shown a montage of his 10 victories before the trophy presentation and said the historic nature of the triumph added to his satisfaction.
Asked if No. 10 was more special than the others, Nadal said yes.
Now 31, Nadal may actually be improving.
"There is nothing to say about today, you were too good".
And then, in the third, Ostapenko again summoned a veteran's resolve, taking the last five games after being down a break at 3-1.
Wawrinka had to come through five sets against world number one Andy Murray in the semi-finals and his body language quickly displayed his frustration as Nadal masterfully whipped balls into hard areas with punishing pace and accuracy - a spinning cross-court forehand putting him 3-0 up in the second set. It was the Swiss player's 17th unforced error. "He won his tenth French Open today, so that's something huge".
At that time, and with his ranking sliding, his grand slam-winning days seemed to be numbered. And he almost won the Australian Open, just falling short at the finish line to Roger Federer. And I miss playing well at Wimbledon.