After James Rockwell's death from typhoid fever at the age of twenty-six, the family moved several times, eventually settling in Asheville, North Carolina.

[3] At the outbreak of World War I, on August 3, 1914, Kiffin Rockwell offered his services to France by letter, which he wrote with his brother Paul, to the French Consul-General in New Orleans.

[3] James Norman Hall, the author of the "History of the Lafayette Flying Corps",[5] suggested that Kiffin Yates Rockwell was the first American who saw military service with France after the beginning of World War I.

Without waiting for a reply, the Rockwell brothers boarded SS St Paul, American Line in New York City and on August 7, 1914 departed for Europe, where they enlisted in the French Foreign Legion.

After recuperating, Paul was transferred to the Allied Press Mission of French Army Grand Headquarters and worked as a war correspondent with the Chicago Daily News.

[6] In his turn, Kiffin requested transfer from the trenches to France's air arm and was among the first Americans to be added to the infant fighter/pursuit squadron which would come to be known as the Lafayette Escadrille.