Under Roman Emperor Domitian (AD 81–96) the Romans pushed east away from the Rhine and the outer boundary of the Roman Empire was set at the Neckar-Odenwald Limes.
The church building of the order that was located on the premises was modified and expanded several times: First in 1350 it was expanded (Gothic), then it was remodeled in 1719 (Baroque), and in 1977, it was consecrated as a cathedral.
Because of the infrastructure thus created, during the 14th century Heilbronn grew attractive to merchants and craftspeople, who now demanded the right to determine their own fate.
In 1371 Charles IV, Holy Roman Emperor, issued a new charter to the city.
The city on the Neckar is a former Imperial Free City and is the seat of Heilbronn County.
Heilbronn is also the economic center of the Heilbronn-Franken region that includes most of northeast Baden-Württemberg.
The name Heilbrunna (healing well) hints to a well that is located not far from the basilica.