Eley is particularly well known for his early study, The Peculiarities of German History (first published in German as Mythen deutscher Geschichtsschreibung in 1984), co-authored with David Blackbourn (a fellow Briton, who now teaches at Vanderbilt University), which challenged the orthodoxy in German social history known as the Sonderweg thesis.
His work identified in the power structures and social relations of agrarian society in Prussia the roots of the authoritarian and undemocratic character of what he, with others, took to be the Sonderweg, or special path of modern German history.