Hillerman, born in Denison, Grayson County, Texas, was the son of Christopher Benedict Hillerman, a gas station owner, and Lenora Joan Medlinger; he was the middle child with two sisters.  His grandfather was the son of German immigrants from Germany and France; and his mother was the daughter of immigrants from Austria and Germany.  Hillerman developed an interest in opera at the age of 10.  He attended St. Xavier's Academy and after graduation attended the University of Texas at Austin for 3 years, majoring in journalism.
Hillerman served 4 years in the United States Air Force (1953-1957), working in maintenance in a B-36 wing of the Strategic Air Command.  During this time he became interested in acting after working with a theatrical group in Ft. Worth.  After his being discharged in 1957, Mr. Hillerman moved to New York to study at the American Theatre Wing and performed in professional theater for 12 years.  Unable to make a living as a stage actor, he moved to Hollywood in 1969.  He worked steadily in motion pictures and television after having his film debut in 1970 under director Peter Bogdanovich in the film "They Call Me Mr. Tibbs."
John returned to his Texas home upon his retirement in 1999.
He died November 9, 2017, at his Houston home. 
He is survived by sister, Jo Ann Tritico; 7 nieces and nephews, including Chris Tritico, a Houston attorney.

source: "John Hillerman."  Wikipedia, viewed January 11, 2018.