From 1890 to 1895, he was a junior lawyer for the regional court districts of Cologne and Frankfurt, with a year off in 1891–1892 for military service.
By 1899, he had attained his doctorate and set about writing a treatise upon the subject of anarchism, for which he was made a professor in 1906.
He suggested in his work Der Bolschewismus und die deutsche Zukunft (1919) that Germany's interests would be best served by adopting a Bolshevik regime.
As a member of the Reichstag, Eltzbacher argued in April 1919 for complete state ownership without compensation.
[1] Eltzbacher was a brother of the author J. Ellis Barker, who emigrated to Britain and gained fame and influence as one of the most active haters of his German homeland.