Another shining light in the music world has gone out today. Raucous soul, visionary artist, and sonic pioneer behind the rise of outlaw country Merle Haggard has died in his home in California, according to a spokeswoman. The music legend died on his 79th birthday.

No cause of death has been determined at this time, though the musician had been in poor health of late, having been in and out of the hospital for months with chronic pneumonia.

“He was my brother, my friend. I will miss him.”

A musical icon whose career began in earnest in the 1960s, Haggard has long been considered one of the best songwriters of all time. In his half century career, Haggard had 40 songs reach the top of the country charts.

A former inmate of San Quentin, Haggard was a teenage runaway who rode freight trains and became a thief — ending up in prison for a botched robbery at the age of 21. He was actually in the crowd at San Quentin when Cash performed there in 1958.

Despite finding a better life in music, Haggard never quite changed his ways, with drug use, bankruptcy, and divorce throwing punches during his long and storied career. Long after his time hopping the real thing, he was reportedly also a longtime model train enthusiast.

An extremely prolific writer who once claimed to have penned over 10,000 songs, Haggard wrote working man’s songs using simple melodies and twangy blues-influenced chords, adding a gritty baritone on top which remained unmistakable throughout his long career. Part of the original band of country outlaws, Haggards cohorts included the likes of Willie Nelson, Kris Kristofferson, Waylon Jennings, Cash, and Hank Williams Jr., among others.

Haggard performed until his recent illness made it difficult to do so — he was forced to cancel all his performances in April due to health issues. But he remained optimistic about getting better, and was even scheduled to tour with Nelson in support of a collaborative album called Django and Jimmie which was released last year.

Merle Haggard - Mama Tried (Live)

“He was my brother, my friend. I will miss him,” said Nelson to TMZ about the news of Haggard’s death.

As news of his passing hits the music world, many more tributes to one of the greatest pioneers of an entire musical generation are sure to follow.

There are just too many great Haggard songs to create a comprehensive playlist of his best hits — in fact, you can probably just scroll through his catalog chronologically — but we’ve gathered of a few of our favorites below for your enjoyment.