Eugen-Heinrich Bleyer was born on 20 November 1896 in Mainz in the Grand Duchy of Hesse, German Empire, as the son of Heinrich Bleyer, a railway inspector, and Elise, née Zilles.

[1] Bleyer commenced his military service on 13 August 1914, shortly after the beginning of World War I, as a Fahnenjunker (officer candidate) in Infanterie-Leib-Regiment „Großherzogin“ (3.

On 8 October 1914, he joined his regiment on the Western Front and was promoted to Leutnant (lieutenant) on 8 May 1915 (with a patent of 22 May 1914).

[1] Bleyer spent the entire war on the Western Front and was wounded five times.

[1] For his achievements, he earned both classes of the Iron Cross, the Wound Badge in Gold, the Hessian General Honor Decoration "For Bravery" and the Hessian Warrior Decoration in Iron.

He was named commander of the 379th Infantry Regiment (Infanterie-Regiment 379) on 17 March 1941 and was promoted to Oberst on 1 January 1942.