Rudolf Frommer was a self-taught engineer and firearms designer who worked his way up through the FEG concern in Budapest to eventually hold the position of CEO. During this time he developed a series of long-recoil, rotating-bolt pistols culminating in the Frommer Stop, which was adopted by the Austro-Hungarian military. These pistols began with the 1901 model (actually patented in 1903), which was a quite large handgun chambered for an early version of the 8mm Steyr cartridge.
The 1901 model Frommer pistol used a 10-round internal magazine fed by stripper clips, and those clips would be a primary reason the pistol was rejected when tested by the US military in 1904. American testing officers complained that the clips were finicky to use, and could easily cause jams if not handled just right (for example, yanked briskly out of the action after charging). The American testing board also criticized the gun for its 8mm cartridge (the Americans wanted nothing less than 11.25mm), and for the weapon not obscuring its sight picture when locking open on the last round.
Only about 200 Frommer 1901 pistols were made before the design was revised in the 1906 model, which was substantially smaller and chambered for a 7.65mm cartridge slightly shorter than the .32ACP. The 1910 model finally achieved a reasonable (if small) serial production of a few thousand guns, The 1912 "Stop" model introduced a much more conventional frame and grip design, and was the breakout success of the series, with several hundred thousand made.