Up to 1808 almost all publications of Field's music were reissues of old works. In 1808–9 he finally began publishing newly composed music, starting with piano variations on Russian folksongs: "Air russe varié" for piano 4 hands, H 10, and "Kamarinskaya" for piano, H 22. In 1811 the composer returned to Saint Petersburg. He spent the next decade of his life here, more productive than ever before, publishing numerous new pieces and producing corrected editions of old ones. He was successful in establishing a fruitful collaboration with both H. J. Dalmas, the most prominent Russian publisher of the time, and Breitkopf & Härtel, one of the most important music publishing houses of Europe. In 1815 Field fathered an illegitimate son, Leon Charpentier (later ), but remained with his wife. They had a son, Adrien, in 1819; Leon would later become a famous tenor, active in Russia, while Adrien followed his father's steps and became a pianist. By 1819 Field was sufficiently wealthy to be able to refuse the position of court pianist that was offered to him. His lifestyle and social behaviour were becoming more and more extravagant.