The Prussian General Staff also enjoyed greater freedom from political control than its contemporaries, and this autonomy was enshrined in law on the unification of Germany and the establishment of the German Empire in 1871. It came to be regarded as the home of German militarism in the aftermath of World War I, and the victors attempted to suppress the institution. It nevertheless survived to play its accustomed part in the German re-armament and World War II.
In a broader sense, the Prussian General Staff corps consisted of those officers qualified to perform staff duties, and formed a unique military fraternity. Their exhaustive training was designed not only to weed out the less motivated or less able candidates, but also to produce a body of professional military experts with common methods and outlook. General Staff–qualified officers alternated between line and staff duties but remained lifelong members of this special organization.
Until the end of the German Empire, social and political convention often placed members of noble or royal households in command of its armies or corps but the actual responsibility for the planning and conduct of operations lay with the formation's staff officers. For other European armies which lacked this professionally trained staff corps, the same conventions were often a recipe for disaster. Even the Army of the French Second Empire, whose senior officers had supposedly reached high rank as a result of bravery and success on the battlefield, was crushed by the Prussian and other German armies during the Franco-Prussian War in the campaigns of 1870–71, which highlighted their poor administration and planning, and lack of professional education.
The Chief of Staff of a Prussian formation in the field had the right to disagree, in writing, with the plans or orders of the commander of the formation, and appeal to the commander of the next highest formation (which might ultimately be the King, or Emperor, who would be guided by the Head of the Great General Staff). This served as a check on incompetence and also served for the objecting officer to officially disassociate himself with a flawed plan. Only the most stubborn commanders would not give way before this threat.
For these reasons, Prussian and German military victories would often be credited professionally to the Chief of Staff, rather than to the nominal commander of an army. Often the commander of an army was himself a member of the General Staff, but it was now institutionally recognized that not only was command leadership important, but effective staff work was a significant key to success in both pre-war planning and in wartime operations.
Before the nineteenth century, success on the battlefield largely depended on the military competence of whichever king was in power. While Frederick the Great brought success to the Prussian arms, his successors lacked his talent, so generalship in the Army declined, even though they were assisted by a Quartermaster General Staff of adjutants and engineers established by Frederick the Great. Reformers in the army began to write and lecture on the need to preserve and somehow institutionalize the military talent that Frederick had assembled in his army. They argued that a carefully assembled cadre of talented officer staff could plan logistics and train the Army in peace as well as in war. In the last years of the eighteenth century, it became the practice to assign military experts to assist the generals of Prussia's Army, largely at the instigation of comparatively junior but gifted officers such as Gerhard von Scharnhorst and August von Gneisenau. Nevertheless, such measures were insufficient to overcome the inefficiency of the Army, which was commanded by aged veterans of the campaigns of Frederick the Great, almost half a century earlier.
In 1806, the Prussian Army was routed by French Armies led by Napoleon's marshals at the Battle of Jena. In the aftermath of this debacle, the Prussian Army and state largely collapsed. "Seldom in history has an army been reduced to impotence more swiftly or decisively.  After the Peace of Tilsit in 1807, King Frederick William III appointed Scharnhorst, Gneisenau, Prime Minister Baron vom und zum Stein and several promising young officers to his Military Reorganization Commission.  This Commission acted as a general staff to plan and implement the reconstruction of the Prussian Army. They persuaded the king that to match the French commanders, who rose by merit, each Prussian commander of an Army, Corps and Division should have a staff-trained officer assigned as his Adjutant. Scharnhorst intended them to "support incompetent Generals, providing the talents that might otherwise be wanting among leaders and commanders". The unlikely pairing of the erratic but popular Field Marshal Blücher as Commander in Chief with Lieutenant General Gneisenau as his Chief of Staff showed this system to its best advantage: Blücher lauded Gneisnau for his role in maneuvering the Prussian Army during a difficult retreat through the Harz mountains.