Prussia from 1813
In Prussia after the Landsturm Edict of 21 April 1813 all the male population from ages 17 to 60 who were capable of military service, who were not in the standing army or the Landwehr, had to respond to the orders of the Landsturm. It effectively formed the last national military reserve.
King Frederick William III of Prussia established the Prussian Landsturm as irregular military forces on 21 April 1813 by royal edict – the decree appeared in the preussische Gesetzesammlung (German: Prussian Code of Law) (pp. 79–89). The 1813 edict called for resistance "by any means" against the Napoleonic invasion. As a model and an explicit example, it took the Spanish Reglamento de Partidas y Cuadrillas of 28 December 1808 and the decree of 17 April 1809, known as Corso Terrestre, during the Peninsula War against Napoleonic troops (ref. the introduction, §8, §52).
According to this edict, all Prussian citizens were obliged to oppose the invasion by the enemy using any weapons available, like axes, pitchforks, scythes or shotguns (§43). All Prussians were further encouraged to not obey orders by the enemy, but rather to make themselves a nuisance to the Napoleonic troops however possible. This was a clear departure from ordinary jus in bello (Latin for Law of War), which commanded the civilian population to obey the orders of the occupying power, and the police forces to assist the occupying power in crushing any uprising. It did not qualify as an insurgency, but simply as criminal activity. The Landsturm edict explicitly stated that it was preferable to risk the danger brought about by the furies of an armed population rather than to let the enemy have control over the situation. Légitime défense "justified the use of all means" (§7), including chaos.
The edict was modified less than three months later on 17 July 1813 and was purified of its subversive content relative to the laws of war. The war then took place according to the standard rules of conventional warfare. Carl Schmitt qualified it as the "Magna Carta of the partisan". Despite its not being put to practice, fascist jurists considered it in a 1962 lecture in Francoist Spain to be the "official document of the legitimation of the partisan of national defense" and as the "philosophical discovery of the partisan." 
The North German Union Act of 9 November 1867 about the obligation for wartime military service and the Reich law about the Landsturm of 12 February 1875 restricted the obligation to the period from 17 to 42 years of age.
Bavaria from 1868
In the Bavarian Army the oldest ages for compulsory military service since the army reform of 1868 was referred to as the Landsturm.
During World War One, the Austro-Hungarian Landsturm consisted of men aged 34 to 55 who belonged to the Austria k.k. Landsturm and the Hungarian k.u. Landsturm. The Landsturm formed 40 regiments totaling 136 battalions in Austria and 32 regiments totaling 97 battalions in Hungary. The Landsturm was a reserve force intended to provide replacements for the first line units. However, the Landsturm provided 20 Brigades who took to the field with the rest of the army.
This hat is a rarity for the Imperial German collector. Made from oil cloth this hat is in great condition for its age. Original Silver German Cross above the Reichs Cockade to the front. Stitching still intact. Liner shows signs of wear but no rips or tears.
It is not very often that these hats come on the market.