NASHVILLE, Tenn. — Country giant Merle Haggard, who rose from poverty and prison to international fame thRough his songs about outlaws, underdogs and an abiding sense of national pride in such hits as “Okie From Muskogee” and “Sing Me Back Home,” died Wednesday at 79, on his birthday.

Haggard’s manager, Frank Mull, said the country icon died in Palo Cedro, California, of pneumonia that he had been battling for months.

He had kept up an ambitious touring schedule, but the pneumonia in both lungs had forced him to cancel several shows this year.

A masterful guitarist, fiddler and songwriter as well as singer, the Country Music Hall of Famer with the firm, direct baritone recorded for more than 40 years, releasing dozens of albums and No. 1 hits.

The White House called Haggard a “legend” and said President Barack Obama was sending his thoughts and prayers to Haggard’s family. White House press secretary Josh Earnest said Haggard told stories that people from all walks of American life could relate to.

“His passing is a loss for country music, but obviously is a loss for all the people who got to know him personally, too,” Earnest said.

Haggard, along with fellow California country star Buck Owens, was a founder of the twangy Bakersfield Sound, a direct contrast to the smooth, string-laden country records popular in Nashville in the 1960s.