A Himalayan thangka, or rolled-up image, is a sacred painting executed in an opaque proteinaceous medium that has a complex mount of textiles and hanging dowels. This study examines the evolution of Himalayan thangka painting materials through analysis of six thangkas dating from the 18th through the 21st centuries. Our analytical methodology includes the use of energy-dispersive X-ray fluorescence (ED-XRF), Fourier transform infrared microspectroscopy (FTIR), Raman microspectroscopy, LC-DAD-MS analysis, high performance liquid chromatography (HPLC), and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS). The 18th–19th century thangkas were prepared with the traditional mineral-based Himalayan palette, including such pigments as azurite, brochantite, antlerite, magnesite, dolomite, kaolinite, orpiment, lead white, lamp black, vermilion, lac dye, and red lead. A 20th century thangka palette included barytes, gypsum, emerald green, and chrome yellow. Non-traditional pigments identified on two 21st century thangkas included Prussian blue, phthalocyanine blue, phthalocyanine green, barium sulfate, titanium dioxide, and chrome yellow. LC-DAD-MS analyses of mounts revealed the use of traditional indigotin, indirubin, and rutin-based dyes as well as a yellow dye with alkaloid components suggesting the plant species <i>Berberis (skyer pa)</i>, which was used in Tibetan medicine and art. While there is documentary evidence for Prussian blue being imported into China in 1759, we have not confirmed the use of synthetic pigments in Himalayan thangkas prior to the 20th century. These materials may have arrived by the ‘Tea and Horse Caravan Road’, on which dyes and chemicals were transported to Lhasa in the second quarter of the 20th century. Additional research on well-dated late 19th and early 20th century thangkas is required to further refine the date of introduction of synthetic artists’ materials into Tibet.