Wehler specialised in research into the Second Reich. He was one of the more famous proponents of the "Sonderweg" (Special Path) thesis that argues Germany in the 19th century underwent only partial modernization. Wehler has argued that Germany was the only nation to be created in Western Europe through a military "revolution from above", which happened to occur at the same time that the agricultural revolution was fading and the Industrial Revolution was beginning in Central Europe. As a result, the economic sphere was modernized and the social sphere partially modernized. Politically, in Wehler's opinion, the new unified Germany retained values that were aristocratic and feudal, anti-democratic and pre-modern. In Wehler's view, the efforts of the reactionary German élite to retain power led to the outbreak of the First World War in 1914, the failure of the Weimar Republic and the coming of the Third Reich.