From Wikipedia:
In October of 1971, newspaper columnist Pete Hamill wrote a piece for the New York Post called "Going Home." In it, college students on a bus trip to the beaches of Fort Lauderdale make friends with an ex-convict who is watching for a yellow handkerchief on a roadside oak. Hamill claimed to have heard this story in oral tradition.
In June of 1972, nine months later, Reader's Digest reprinted "Going Home." Also in June 1972, ABC-TV aired a dramatized version of it in which James Earl Jones played the role of the returning ex-con. A month-and-a-half after that, Irwin Levine and L. Russell Brown registered for copyright a song they called "Tie a Yellow Ribbon Round the Ole Oak Tree." The authors said they heard the story while serving in the military. Pete Hamill was not convinced and filed suit for infringement.
One factor that may have influenced Hamill's decision to do so was that, in May 1973, "Tie A Yellow Ribbon" sold 3 million records in three weeks. When the dust settled, BMI calculated that radio stations had played it 3 million times--that's seventeen continuous years of airplay. Hammill dropped his suit after folklorists working for Levine and Brown turned up archival versions of the story that had been collected before "Going Home" had been written. [1]
I'm sorry folks, but I got curious and had to research more about the yellow ribbon business.
The idea of a yellow ribbon for a soldier far, far away...basically came from the WW2 US Army cadence song in which "yellow" fit the music better than white. "Around her neck, she wore a yellow ribbon...she wore if for her soldier who was far, far away." The John Wayne movie of 1949 cleaned up the lyrics a bit. The original song was about her being preggie and unmarried while the soldier is away.
And that US Army cadence song must have evolved from an 1838 British song called "All Round My Hat" that goes like this: "All round my hat I [w]ears a green willow [because] my true love is far, far away."
It took 105 years for "green willow" to become "yellow ribbon".
Somehow the yellow ribbon idea for women staying faithful to soldiers...migrated into the convict community after World War Two. It remained below the surface of our society (in the convict world) until it started getting attention as an urban legend in the early 70s with a story going around about a convict who couldn't bear to look at a tree to see if his woman wanted him back as a sort of prodigal son.
With soldiers coming home from Vietnam, and treated like dirt by a lot of the population, the Tony Orlando and Dawn song, in May 1973, was a smash hit!! The returning veterans angle probably had a lot to do with the success of the song.
But, after the song was a hit, the first known instance of a yellow ribbon getting media attention was when a Watergate convict's wife put up a yellow ribbon (Mrs. McGruder). It was because of this act that the wife of an Iranian hostage decided to do the same thing in 1979. This Iranian hostage wife was on a TV report that showed the yellow ribbon around the big tree in her front yard.
And that was all she wrote. Today...it is a major American symbol of remaining loyal to someone who is far away in harm's way or going through a lot.