Caïn was born in Paris, and studied under Rude, Guionnet, and Pierre-Jules Mêne (whose daughter he married in 1852).
From 1868 onwards he concentrated on monuments, including the Chiens de meute at the Château de Chantilly, Le Lion de Nubie et sa proie in the Jardin du Luxembourg, and Tigress and Peacock in the Gardens of the Tuileries.
In 1879 he assumed management of his father-in-law's foundry upon Mêne's death.
Henri Caïn, a well known librettist, and Georges Cain, the painter, were his sons.
Media related to Auguste Cain at Wikimedia Commons