In 1495, an attempt was made at an Imperial Diet in the City of Worms to give the disintegrating Holy Roman Empire a new structure, commonly referred to as Imperial Reform (German: Reichsreform). The fundamental idea of the reform was largely based on the theory of inter-political concordance between the Emperor and the Imperial States developed by Nicholas of Kues.
After the fall of the House of Hohenstaufen in the mid-13th century the Emperors had to face a continuous loss of power in favour of the estates, especially of the Prince-electors assigned by the Golden Bull of 1356. The autonomous Reichsstände nevertheless had painfully become aware of the disadvantages in the defiency of a centralised authority on the occasion of threats and armed conflicts like the Hussite Wars.
Maximilian I of Habsburg, elected King of the Romans since 1493, after 1477 had to defend his claims to the heritage of his deceased wife Mary of Burgundy against intriguing Louis XI of France, while subsequent to the 1453 Fall of Constantinople the expansion of the Ottoman Empire on the Balkans proceeded. At the 1495 diet Maximilian asked the representatives of the estates not only for contributions, but also for the implementation of an imperial tax and commitment in troops. The deputies, led by Chancellor Bertold von Henneberg-Römhild, the Archbishop of Mainz, in principle agreed on a Common Penny (Gemeiner Pfennig) tax paid directly to the Empire but in return set conditions:
The Swiss Confederacy did not accept the resolutions of the Imperial Diet and explicitly refused to pay the Common Penny, one of the circumstances leading to the Swabian War of 1499 and the Confederacy's exemption from imperial legislation. Due to the obstinate resistance of several States the collection of the tax was finally suspended in 1505.
Whether the Reform can be considered successful depends on how its goals are defined; today, many scholars believe that the Reform was not really aimed at producing a modern state (in which it would be considered a failure), but rather attempted to consolidate and distribute power between the Empire and the States by consensus, an aim in which it did succeed.
The reform was more or less concluded with the Imperial Execution Order of 1555, part of the Peace of Augsburg, which regulated more details of the tasks of the Imperial Circle Estates.