This unique and adorable inkwell is modeled after the Prussian Garde du Corps / Garde Cuirassier 1867 helmet. I would date it ca.1890-1910. Undoubtedly, it once sat on a writing desk of a high-ranking German Imperial officer.
Quality of casting and the fine detail of the hand-chasing of the eagle is quite remarkable. This inkwell has all the attributes of being a presentation gift to a high ranking officer. Condition is wonderful, with signs of honest wear.
You may never see another one!