Pharrell Williams Cries 'Happy' Tears During Oprah Interview (VIDEO)

REUTERS/JONATHAN ALCORNSinger Pharrell Williams gestures as he attends the Museum of Contemporary Art (MOCA)'s 35th Anniversary Gala presented by Louis Vuitton at The Geffen Contemporary at MOCA in Los Angeles, California March 29, 2014.

Pharrell Williams' "Happy" song caused him to start crying during an interview with Oprah Winfrey on her OWN station Sunday. The 41-year-old musician, producer and singer had been listening to his song being played around the world when he became overwhelmed.

Pharrell Williams' hour-long interview with Oprah showed the two discussing his hit song, "Happy," which he said wasn't popular before he released the music video. The now-famous video shows Pharrell and regular, everyday folks dancing around to the innocuous lyrics.

Soon, people were releasing their own versions of the music video from Slovakia to Dakar, Senegal to Detroit to Portugal to Taiwan, and when Williams saw the clip, he started crying.

"Why am I crying on Oprah?" Williams said while wearing a green version of his Vivienne Westwood cowboy hat. "It's overwhelming because I love what I do and I just appreciate the fact that people have believed in me for so long that I could make it to this point, to feel that."

It wasn't always that way. Pharrell used to be much more behind the scenes while working with major artists like Jay Z and Gwen Stefani while also making his own music with N.E.R.D. collaborator Chad Hugo. Even as recently as last year with Robin Thicke's hit "Blurred Lines," Williams was comfortable not being the star.

"I was happy being the guy standing next to the guy," he said.

Oprah also discussed his new album, G I R L, his Oscar nomination for "Happy" – it was on the soundtrack for Despicable Me 2 – and his marriage to longtime girlfriend Helen Lasichanh, mother of his son, Rocket. Williams revealed the meaning behind his 4-year-old's unusual name as well.

"In the same way the Indians named their children after a force or animal or element, we named him after a man-made machine that was meant to go up, meant to ascend," he said.