Browning Hi-Power
9x19mm or 7.65x21mm Parabellum or .40 S&W
Designed by John Browning for the French it was ready in 1935 but rejected by the French and adopted by Belgium. Since WW II however it became one of the most influencial pistols with a 13-round staggered magazine (nearly double that of the M1911).
It is the standard sidearm of the Belgian Army, the British Army (alongside the SIG-Sauer P226), Indian Army, Australian Defence Force, Argentine Army, Luxembourg Army, Israel Police, Singapore Armed Forces and Venezuelan Army, among others. The Irish Army only replaced them with the H&K USP automatic in 2007.