"The Portuguese Jesuit Tomás Pereira (1646–1708) was summoned to Beijing in 1672 and served at the court of the Kangxi Emperor for more than three decades, renowned as a musician, clockmaker and interpreter and appointed the emperor's first music teacher. In 1689, with Jean-François Gerbillon, he served as interpreter and adviser in the Sino-Russian negotiations at Nerchinsk. In gratitude for the missionaries' service, Kangxi issued the Tolerance Decree of 1692, easing restrictions on Christian practice."