He was born December 1, 1978
Mat began focusing on music fusing his simple guitar playing with spoken word, or rap, he started to play at coffee shops and soon began to make small amounts of money. At this time, Mat had met friend and future producer, Robert Marvin. The two began to make music together, but Marvin had plans to move to Nashville, Tennessee. Marvin asked Kearney to help the move and Mat accepted the journey. Kearney says, "I helped him pack up his trailer and we put a mattress on the back of his truck. We basically drove cross-country and slept in the back. When we pulled into Nashville we slept in a school parking lot for three days until we finally rented this apartment where the roof was caving in and mice were crawling all over." Mat decided to stay in Nashville to record a few demos with Marvin and after a few months, Mat had no plans on returning. "By the end of the summer, we had three or four songs and I realized this is what I wanted to do. It just clicked. So I called home to Oregon and said, ‘I’m not coming back’ and I never left Nashville."
While record labels were starting to offer Kearney development deals early on, he wanted to wait until he had his new material at a higher level. "I knew my songs weren't quite there yet, so instead, I worked every kind of odd job you can think of. I worked at a coffee shop, was a banquet server, worked as a youth mentor with kids. But I kept working on music," he says. "I tried to devote time to write and to perform at the same time. I started by playing these songwriting nights and performing my songs around people like Nickel Creek and Duncan Sheik. Living in Nashville really stepped up my songwriting."
It took about four years, but once Kearney felt he had his songs right, he completed his first album, Bullet, on a self-financed, shoestring budget. The album would go on to sell roughly 40,000 copies through an independent label in Nashville. The response to his songwriting was instantaneous and lead to a record deal with Aware/Columbia Records.