Gayl was born in Königsberg, capital of the Prussian province of East Prussia (today Kaliningrad, Russia) and studied law at the universities of Berlin, Göttingen and Bonn.

[1] He served throughout the First World War, initially as an officer on active service, and was decorated with the Iron Cross first class, but soon joined the administration of Ober Ost as Supreme Commander of All German Forces in the East.

In 1916 he became Chief of the Department of interior politics and administration of Ober Ost and on 1 September 1918 Landeshauptmann ("State Captain") of northern Lithuania at Kaunas.

Papen used this opportunity eighteen times in the six months of his term in office while he never spoke at the Weimar German Parliament[3] Gayl was one of the initiators of the Preußenschlag against the Social Democratic government in Prussia in June 1932[4] but strongly opposed any cooperation with Hitler's Nazi Party.

Before the August 1919 abolition of nobility as a legal class, titles preceded the full name when given (Graf Helmuth James von Moltke).