Staff Writer (Updated: 9/13/2016):
The original P08 production models were chambered to fire a 7.65mm round and were adopted by the Swiss Army as early as 1900. The more recognized version of the Luger became the Pistole 1928 designation, as it was the adopted production model of the year 1908. This model in itself was an improved version of previous generation 9mm pistols known as 'neuer Art'.
In 1914, the P08 production began appearing from other lines as in the Koniglich Gewehrfabrik Erfurt series, and it was about this time that the optional shoulder stock came into the design.
Despite the restrictions set aside by the Treaty of Versailles regarding Germany's defeat, the pistol continued to be made, either within the German border or in production lines elsewhere in Europe - by this time chambered for the more known 9mm Parabellum round. The British even produced the P08 model series of pistols through the Vickers-Armstrong and Company firm with parts supplied from Germany. These versions were eventually shipped through Holland for the Netherlands East Indies armies abroad.
The P08 series proved to be an extremely reliable and robust handgun, considering the locking device was of a complicated design. This fact also proved the P08 to be extremely complicated to produce in the numbers required during war time. Reports were, however, favorable as to the firing action of the system, allowing for an easy of use in the point-and-shoot department.
The Luger would continue to be produced right up to the opening years of the Second World War when its ultimate successor - the Walther P38 was starting to come around. Official production of P 08 Luger's would last until 1942 with a total of some two million models produced including variants and sub-variants.
The Luger would go on to become a collector's favorite hand gun with some of the prize collectors being Allied troops themselves - confiscating the hand gun as a trophy of their exploits in and throughout the war. Though expected to be replaced in large numbers by the oncoming Walther P 38, production numbers of that pistol never materialized to expected levels, allowing the Luger to be found in most frontline and reserve situations.
In the end, the pistol has proven to stand the test of time, resurfacing every now and again under production by some company around the globe. A specialized variant of theP 08 series existed as the P17 Artillerie model which featured a barrel 8-inches longer than the standard P 08. This variant was designed to hold a full 32-rounds of ammunition (held in a drum magazine) though it was not in production by the time the Second World War rolled around.