How did Ed Sheeran become famous?

[Who]

I've heard many reasons why, I've heard X-Factor, One Direction pretty much promoted him, him getting fame from Twitter, YouTube, I seriously have no idea. I think he's a pretty good singer, I just wanna know how he rose to fame really!

[Sam]

By writing amazingsongs duhh!

[jenna a]

It could be anything, but I think he worked his butt off. So it doesn't matter how he became famous.
I didn't know who he was until I first heard his song "The A Team". I fell in love with it instantly.