The Boxer's exact origins are a bit sketchy; however, it is commonly believed that the Boxer's immediate ancestors include dogs from the Bullenbeisser-type. These dogs were used in Germany for hunting and could hold a large animal until the hunter arrived to kill the beast. The Danziger Bullenbeisser was used in northern Germany an Poland, according to the [German] Boxer Klub; the smaller, more agile Brabenter Bullenbeisser was used to hunt wild boar in southern Germany. The smaller of these two types is believed to be a progenitor of the breed.

The Bullenbeisser, which hunted with noblemen prior to 1803, was then used to help butchers with their livestock later in the 1800s. The Boxer's new role saved the breed from extinction, according to the Boxer Klub. It was around this time that the English Bulldog was introduced to the Bullenbeisser breeding line, imparting its white coloring and markings to previously fawn or brindle Bullenbeissers. With the introduction of the English Bulldog, the Boxer we know today began to take shape.

A Boxer club had been formed in Munich in 1895, and the founders drew up the first Boxer Standard as a guide for their future breeding.