First flown on December 14th, 1914, the military-minded Zeppelin "LZ-26" became one of the more successful of the German Empire Zeppelins of World War 1. it was used as a reconnaissance and bombing platform over the Eastern Front against the Russian Empire and against the Allies on the Western Front, particularly over Northern France. The airship served under the tactical designation of Z XII and was born from the "Type N" class. As a bombing platform, it claimed some 44,100lbs of ordnance dropped in the war across eleven total missions. Despite these successes, the age of the Zeppelin as a useful frontline bombing platform was more or less over - it was formally decommissioned on August 8th, 1917.
LZ-26 took on the established shape of Zeppelins with tapered ends - the frontal section a nose cone and the aft section finned for stability control. These ends capped a tubular body consisting of a metal skeletal structure covered over in fabric. Lifting was accomplished through use of hydrogen-filled cells with the skin of the airship - hydrogen proving useful for the role though highly flammable in turn. When the Allies began wider spread use of incendiary ammunition, this became a very real and lethal problem for German airship crews. The crews were housed in under-slung gondolas containing armament stores and defensive weaponry while engines (providing the necessary forward propulsion) were held out and away from the fuselage by way of struts. Despite their climbing ability and valuable "over-the-horizon" qualities from a tactical sense, the more advanced Allied aircraft and improved ground-based anti-aircraft fire began to severely marginalized airships as useful battlefield weapons.
The airship concept was pioneered by German Count Ferdinand von Zeppelin (hence its popular common name of "Zeppelin"). The concept first emerged in useful form as early as 1874 before being finalized in 1893 while a German patent proved forthcoming in 1895. First commercial use of Zeppelins in the airliner role began in 1910 - roughly four years before the war.