Heinrich Roth's Sanskrit grammar, that he had completed by 1660 in Latin language under the title Grammatica Linguae Sanscretanae Brachmanum Indiae Orientalis (the manuscript of which is preserved today at the Biblioteca Nazionale Centrale in Rome) and that was augmented by preliminary studies for a complete Sanskrit-Latin dictionary, made him a pioneering scholar in modern Sanskrit studies in Europe. Further works include studies on the Hindustani and Devanagari alphabets, on Vedanta and on Vishnu. Also, a total of 35 letters, written by Roth from India and during his travel back to Europe, survive at the Royal Library of Belgium in Brussels.