The Luger U-08 pistol is a very recognizable pistol and is usually associated with Nazi Germany and WWII. It was patented in 1904, and is an improvement of an earlier automatic pistol, the 1893 Borchardt C-93 pistol.
German born Hugo Borchardt emmigrated to the U.S. when he was 16, and worked in various engineering and machining positions for Pioneer Breechloading Arms, Singer, and Sharps (where he designed the Sharps-Borchardt rifle). In 1893 , when Borchartd was 49, he moved to Hungary to accept a job with a gun manufacturer named Ludwich Lowe, and there he designed the C-93 semi-automatic pistol.
The C-93 was made in some quantity, but was never accepted for sales to any country's military.
Austrian born Georg Luger worked with Ferdinand von Mannlicher in designing rifles and pistols, and went to work for Ludwich Lowe, the same company the made the C-93. Luger demonstrated the C-93 to U.S. Army representatives in 1897, and listened to the C-93 being criticized for weight, comfort of the 90 degree handle, and doubts about the small caliber bullet. Luger took those criticisms and redesigned the C-93 into the 9mm Luger U-08. The Luger was patented in the U.S. in 1904, and is the basic form of the Luger used in WWI and WWII.
The Luger was tested for use by the U.S. Army shortly after 1900, but was beaten in the trials by the incredibly rugged Colt 1911. The tests were particularly gruelling, and highlighted the main difference between the Colt 1911 and the Luger. The Luger was accurate, but complicated, with very close tolerances, and very prone to malfunction when dirty. The tests involved shooting in dirt, mud, acid and misshapen rounds, and firing several series of 6000 rounds non-stop, and in that environment the Colt 1911 was superb by comparison.
However the Luger was approved by the German Army, and saw service in WWI and WWII.