The oldest traces of humans in and around Heilbronn date back to the Old Stone Age (30,000 BC). The fertile Neckar floodplains in the Heilbronn basin aided early settlement by farmers and ranchers. The city limits of present-day Heilbronn contain many sites of Bronze Age finds. Later on, but still before AD, the Celts already mined here for salt from brine.
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. A castle in today's borough of B�ckingen was part of that limes, and nearby numerous Roman villas and plantations were built. Around AD 150, the Neckar-Odenwald-Limes became obsolete when the boundary of the Roman Empire was moved approximately 30 km to the east, where it was subsequently fortified with the construction of the Upper Germanic Limes complete with parapet and trenches.
Around 260, the Romans surrendered the limes, and the Alamanni became rulers of the Neckar basin. Between the 4th and 7th centuries, the area became part of the Frankish Empire, and the first settlement was built in the general vicinity of the present center of town.
In 741 Heilbronn is first mentioned in an official document of the Diocese of W�rzburg as villa Helibrunna (together with a Michaelsbasilica), and in 841, King Louis the German set up court here for a period of time. The name Heilbrunna (healing well) hints to a well that is located not far from the basilica. In 1050 a significant settlement of Jews is noted in official documents, and the Codex of the monastery in Hirsau documented Heilbronn's right to hold market days and mint coins, mentioning its harbor and vineyards as well.
In 1225 Heilbronn was incorporated into the Hohenstaufen Empire as oppidum Heilecbrunnen. Oppidum signified a city fortified by parapet and trenches. Later during the 13th century, the Teutonic Knights obtained ownership of a large area south of
