Shafer, born Sanger D. Shafer on Oct. 24, 1934 in Whitney, Texas, died Saturday at the age of 84, according to reports out of Nashville.
There is no information yet on Shafer's cause of death.
Shafer grew up in Texas as the son of two Gospel singers, the style he first learned to sing. Later, he did a stint in the Army and worked odd jobs like digging ditches and raising turkeys.
His first hit after lighting out for Nashville in 1967 was "Tell Me My Lying Eyes Are Wrong," which was a No. 13 hit on the Billboard charts for George Jones in 1970. He would continue to do work on the side to supplement his living as a songwriter.
Shafer would go on to collaborate with country legends such as Lefty Frizzell, Connie Smith, Johnny Russell and Merle Haggard, but the songs he's most known for to many Texans are "All My Exes Live in Texas" and "Does Fort Worth Ever Cross Your Mind," recorded by George Strait.
According to country music lore, it was Shafer's three divorces in the 1980s that helped him write those two songs for King George. Both songs became No. 1 hits for Strait.
In the 1990s and 2000s, Shafer's influence diversified. He went on to pen songs recorded by artists like Kenny Chesney ("Between Midnight and Daylight"), Lee Ann Womack ("Thinkin' With My Heart Again") and John Michael Montgomery ("Beer and Bones"), and his original recording of "All My Exes" was included in the "Grand Theft Auto: San Andreas" video game.