Warbasse did postgraduate work under surgeon Franz König and pathologist Johannes Orth in Göttingen, Germany and in Vienna, Austria under Theodor Billroth.

Though born into the privileged class of early New England heritage, Warbasse was a tireless advocate for social equality and economic democracy.

[3] Warbasse founded the Cooperative League of the U.S.A. in New York City in 1916 with his wife Agnes, baker and author Alfred Sonnichsen and other progressive organizers.

Warbasse, genuinely seeking a solution to the world's inequalities, ultimately rejected socialism, anarchism and radical unionism in favor of cooperative economics as the best model for creating an inclusive economy in the context of preserving personal freedom and political autonomy.

[4] The Kings County Medical Society apologized to Dr. Warbasse in 1930, rescinded his expulsion and expunged from their records all evidence of their having expelled him.

The home he shared with his wife Agnes and their six children, bustled with the comings and goings of neighborhood pals and distinguished guests.

[1] Warbasse wrote many books throughout his career, including a three volume text on surgical practices and about 100 scientific and clinical papers.