On 10 August 1915, during the First World War, Jelínek was enlisted into the Austro-Hungarian 8th field regiment (Moravian).

He joined the Czechoslovak Legions at Menzelinsk on 22 August 1917 after being captured by the Imperial Russian Army.

After the war Jelínek moved to Boskovice, worked as a revenue clerk, and wrote for a newspaper.

Jelínek researched the book by interviewing other former legionnaires, gaining insight into their lives after the war, their experience in the legions, and their motivations for joining.

Jelínek made his last public appearance on 25 October 1968 during a celebration of Czechoslovakia's 50th anniversary.