The music world mourns the loss of country music legend Merle Haggard.
Best known for celebrating outlaws, underdogs and having an abiding sense of national pride in such hits as "Okie From Muskogee" and "Sing Me Back Home," Haggard died of pneumonia Wednesday at 79, on his birthday.
Take a look at what the stars had to say about his passing.
Country music has suffered one of the greatest losses it will ever experience Rest in peace Merle Haggard
— Charlie Daniels (@CharlieDaniels) April 6, 2016
literally just fell to the floor. can't believe we lost the hag. rip merle haggard
— Dierks Bentley (@DierksBentley) April 6, 2016
"Mighty" Merle Haggard was the greatest country songwriter of ALL TIME. We shared many great memories, and I will miss him. #merlehaggard
— John Rich (@johnrich) April 6, 2016
Hard to believe the news about Merle Haggard. Working with him is something I'll never forget & will cherish forever pic.twitter.com/XsgqYvbtD5
— Dustin Lynch (@dustinlynch) April 6, 2016
There will never be another artist like the Hag... Rest In Peace Merle Haggard
— ChrisYoungMusic (@ChrisYoungMusic) April 6, 2016
We lost one of the best today. Rest in peace Merle Haggard.... You will be missed pic.twitter.com/672bX7VSEy
— Tyler Farr (@tylerfarr) April 6, 2016
My heart is absolutely broken in two at the news of the loss of Merle Haggard. We keep losing all of the good ones. What a sad, sad day...
— Jay DeMarcus (@JayDeMarcus) April 6, 2016
Rest in peace, Hag. One of a kind, and the definition of legend. pic.twitter.com/aUGX22Avna
— Trisha Yearwood (@trishayearwood) April 6, 2016
There are no words to describe the loss & sorrow felt within all of music with the passing of Merle Haggard. Thank God for his life & songs.
— Brad Paisley (@BradPaisley) April 6, 2016
“Jesus… Sweet Jesus…You love me just as I am… Jesus… Sweet Jesus… I’ve been washed in the Blood of the Lamb!” Merle Haggard #RIPHAG
— The Oak Ridge Boys (@oakridgeboys) April 6, 2016
You are a cornerstone of country music @merlehaggard...u will be missed greatly. Praying for the Haggard family. ��— Hillary Scott (@HillaryScottLA) April 6, 2016
He was more than a great talent. He was a gifted poet. What a huge inspiration he was to everyone! RIP Merle Haggard pic.twitter.com/AneyiMgdsh— Travis Tritt (@Travistritt) April 6, 2016
Merle Haggard is the reason I do what I do. I can’t believe he’s gone. pic.twitter.com/RdzbvtWwLg— Josh Thompson (@TheJoshThompson) April 6, 2016
Merle Haggard was the best country songwriter there ever was.— Jason Isbell (@JasonIsbell) April 6, 2016
Love and prayers for the Haggard family. Merle was a pioneer...a true entertainer...a legend. There will never be another like him.— Carrie Underwood (@carrieunderwood) April 6, 2016
@merlehaggard you will be missed. Thank you for showing us how a country song should be lived, written and sung.— Eric Paslay (@ericpaslay) April 6, 2016
Merle Haggard— Granger Smith (@GrangerSmith) April 6, 2016
Your name will be honored. Your music celebrated. Your legacy never forgotten. Country music will live on. I'll be sure of it.
Sad day for country music! Merle Haggard is the greatest of all time...period! RIP Merle pic.twitter.com/A3KK0n5qwP— Craig Campbell (@craigcampbelltv) April 6, 2016
Sad day today @merlehaggard has passed. RIP to a true songwriter, a pioneer of California Country, and country music.— Jon Pardi (@JonPardi) April 6, 2016
The Associated Press contributed to this report.