Aurin was first prepared in 1834 by the German chemist Friedlieb Ferdinand Runge, who obtained it by distilling coal tar.  He named it Rosölsäure or Rosaölsäure (red oil acid).  In 1861, the German chemists Hermann Kolbe and Rudolf Schmitt presented the synthesis of aurin by heating oxalic acid and creosote (which contains phenol) in the presence of concentrated sulfuric acid.  (Gradually, chemists realized that commercial aurin was not a pure compound, but was actually a mixture of similar compounds.)
Aurin is formed by heating of phenol and oxalic acid in concentrated sulfuric acid.