Heinrich Caro develops a synthesis for alizarin (a natural pigment in madder), and applies for a British patent on June 25, 1869.

BASF had recruited Caro, a German chemist with experience of the dyestuffs industry in England.

Coincidentally, William Henery Perkin applies for a virtually identical patent on June 26, 1869, and the two companies come to a mutual commercial agreement about the process.

BASF, which stands for Badische Anilin- und Soda-Fabrik (English: Baden Aniline and Soda Factory), had been founded on April 6, 1865 in Mannheim, in the German-speaking country of Baden by Friedrich Engelhorn, who had been responsible for setting up a gasworks and street lighting for the town council in 1861.

The gasworks produces tar as a byproduct, and Engelhorn uses this for the production of dyes.

BASF had been set up in 1865 to produce other chemicals necessary for dye production, notably soda and acids.

The plant, however, had been erected on the other side of the Rhine river at Ludwigshafen because the town council of Mannheim was afraid that the air pollution of the chemical plant could bother the inhabitants of the town.

In 1866, the dye production processes had also been moved to the BASF site.

The discovery in 1856 by Perkin that aniline could be used to make intense coloring agents had led to the commercial production of synthetic dyes in England from aniline extracted from coal tar.