Lieutenant John Lyon grew up in Arlington, living with his sister and their parents. After attending the University of Virginia, he was associate editor of Field and Stream and worked out of New York. When the war broke out in 1915, he went to Belgium and became a Red Cross ambulance driver. Several years later, when the U.S. entered the war, he returned home and rejoined his company, the Alexandria Light Infantry, which later became part of the Twenty-ninth Division. Lyon saw considerable action when his regiment was sent to France, and he was killed in October 1918. General Orders, No.22. were issued by the War Department on April 20, 1920.

According to The Washington Post, a citation read: John Lyon, first lieutenant, Machine Gun Company, 116th Infantry, Twenty-ninth Division. For extraordinary heroism in action near Damogneux, France, October 15, 1918. During the attack on the Bois De La Grande Montagne, Lieut. Lyon left a place of comparative safety to cross an open space, exposed to direct observation and fire from the enemy, to attempt the rescue of a wounded officer. He and the two men who accompanied him were killed in this attempt.
Lieutenant Lyon was awarded the Distinguished Service Cross posthumously for his actions that Day. He is buried in the Lyon family plot at Historic Blandford Church in Petersburg, VA. A memorial to John Lyon --- and several others --- stands across the street from the Safeway on Langford Boulevard on the grounds of the Cherrydale Nursing Home in Arlington, VA. Post 3150 holds a special ceremony at the memorial every Memorial Day and Veterans Day.
"...But it is down at the post de secor* themselves that you can see war itself pressing on men's minds. They never laugh down there. All is grim, and the poor wrecks who tumbled in or straggled down the gutted roads have no story to tell. They sing no songs and bring no captured banners back: only memories of lives offered on fiery alter and what satisfaction comes of having killed someone you never learned to hate. They have seen war and know what it is like, so they do not smile anymore."

John Lyon
August 15, 1915
Westvletern, Belgium
* post de secor - aid station