The Prussian Reform Movement was a series of constitutional, administrative, social and economic reforms early in the nineteenth-century Kingdom of Prussia. They are sometimes known as the Stein-Hardenberg Reforms, for Karl Freiherr vom Stein and Karl August Fürst von Hardenberg, their main instigators. Before the Second World War, German historians, such as Heinrich von Treitschke, saw the reforms as the first steps towards the unification of Germany and the foundation of the German Empire.
The reforms were a reaction to the defeat of the Prussians by Napoleon I at Jena-Auerstedt in 1806, leading to the second Treaty of Tilsit, in which Prussia lost about half his territory and was forced to make massive tribute payments to France – to make those payments, he needed to rationalize his administration. Prussia's defeat and subjection also demonstrated the weaknesses of his absolutist model of statehood and excluded him from the great powers of Europe.
To become a great power again, it initiated reforms from 1807 onwards, based on Enlightenment ideas and in line with reforms in other European nations. They led to the reorganization of Prussia's government and administration and changes in its agricultural trade regulations, including the abolition of serfdom and allowing peasants to become landowners. In industry, the reforms aimed to encourage competition by suppressing the monopoly of guilds. The administration was decentralised and the nobility's power reduced. There were also parallel military reforms led by Gerhard von Scharnhorst, August Neidhardt von Gneisenau and Hermann von Boyen and educational reforms headed by Wilhelm von Humboldt. Gneisenau made it clear that all these reforms were part of a single programme when he stated that Prussia had to put its foundations in "the three-faced primacy of arms, knowledge and the constitution".