Almost fifty years later, in 1867, Wilhelm and Paul Mauser invented a novel bolt system for breechloaders. This weapon was introduced as the German infantry weapon M71 in 1871. In 1897, the royal weapons factory became Waffenfabrik Mauser AG. The 20th century saw the factory expanded and a new product line, an infantry weapon model 98, was introduced. In 1945, the former royal weapons factory was dismantled by French occupying forces. Edmund Heckler, Theodor Koch and Alex Seidel, former Mauser engineers, saved what they could from the ruins, thus laying the foundation for what was to become Heckler & Koch.

Heckler and Koch GmbH (HK) was registered in December of 1949 and officially opened for business in this historical center of German gun-making enterprise in 1950. In the aftermath of World War II, the new firm would eventually help rebuild a nation destroyed by war. Founded in an engineering office of the former air-raid protection of the Fire Brigade warehouse, HK’s early product line featured parts and spares for household machines and bicycles. However, this range of products was soon expanded to include the design and manufacture of gauges and specialized tooling.

Soon, HK’s dedication to innovating and developing products of the highest engineering and quality standards resulted in the development of their first firearm, the G3. By 1959, the G3 was the standard issue assault rifle for all German forces by the Bundeswehr of the Federal Republic of Germany. The G3 used the unique delayed-locked roller bolt system; an operating system widely hailed today for its strength, reliability and low recoil. Used by the military in more than fifty nations, some three million G3’s have been produced to date.

And, in the mid-1960s, HK gained international prominence with the design and manufacture of the 9 mm Machinenpistole 5 (MP5), soon to become the world’s most popular submachine gun, embraced by special operations forces worldwide. A variety of models have been added over the past thirty years but the MP5 remains the preeminent arm of its class.

Also during the 1960s, HK perfected the polygonal profile barrel. Deemed superior to conventional "lands-and-grooves" rifling, the polygonal bore profile effectively seals propellant gases behind the bullet – increasing bullet velocity. An added advantage to the polygonal profile barrel is that it will outlast a "lands-and-grooves barrel" by thousands of rounds.

Handgun development also commanded the attention of HK designers and engineers during these years. In 1969, a reworking of the delayed-locked roller bolt system was introduced in a pistol - the P9S. Acclaimed for its accuracy, the P9S was officially embraced by several elite military units, including the US Navy SEALS. However, the most radical feature of the P9S was its design. The receiver was designed using a newly developed high-tech plastic composite called polymer, which molded around the steel frame. With the development of another polymer framed HK handgun, the futuristic VP70, these models predated by more than fifteen years the introduction of polymer framed handguns by competing firms.

In 1976, Heckler & Koch Inc., a U.S. company with headquarters in Arlington, then Chantilly and finally Sterling, Virginia was established to serve the needs of the U.S. military, law enforcement and civilian markets.

HK innovation continued and, in the late 1970s, the HK P7 was introduced into the U.S. and international markets. The P7 was considered quite radical in design and technology, and today it remains the fastest and most accurate production handgun manufactured.

During the 1980s, the precision accuracy found on the HK91 and its related variants, the SR9T, the SR9TC and PSG1 enabled target shooters to achieve performance unmatched in semi-automatic rifles.

The renowned Universal Self-loading Pistol (USP) debuted in early 1990. Considered HK’s first pistol designed especially for American shooters, the USP incorporates many traditional handgun design elements with advanced materials and engineering technology. Equally respected is the Mark 23, developed during 1990 for the US Special Operations Command (SOCOM) using much of the technology and engineering knowledge gained in creating the USP. In 1997, the USP Compact joined the standard frame USP line, winning plaudits for a full hand-grip and other user innovations. The USP Compact has since been adopted by many federal law enforcement agencies.

The close of the 20th century clearly signaled that the innovation and the technology which founders Heckler, Koch and Seidel had established showed no sign of abating. 1999 marked the first time since World War II that German soldiers were in combat. Using the newly developed Heckler & Koch G36 5.56mm rifle, German army units fought in support of human rights and social justice during NATO’s ground deployment in Kosovo.

The 21st Century brought corporate changes to Heckler & Koch. Though the product line remains the same, the ownership has changed. BAE Systems sold Heckler & Koch to a group of investors, two of whom have assisted with the growth of Heckler & Koch for more than 20 years.

After only a few months of ownership, these individuals expressed their desire to have Heckler & Koch products be manufactured in the United States in addition to Germany. On October 14, 2003 HK's Ernst Mauch and Peter Simon broke ground at the Columbus, Georgia site location with some of Columbus' local government officials on hand, as the start of a new era in HK's ability to provide the American military, police and civilian market with uncompromising product availability, service and support for the 21st Century.