Sixtus is a historian specialising in Czech and Central European history from the 18th to the 20th centuries. He earned his PhD in Czech history from the Masaryk University for a dissertation published as Freedom of Conscience. Superintendent Michael Blažek and the Protestant Society of the Late Enlightenment (Svoboda svědomí. Superintendent Michael Blažek a protestantská společnost pozdního osvícenství, 2016). He teaches at the Faculty of Pharmacy of Charles University, focusing on the Enlightenment and its significance in the field of public healthcare.
Within PragMatika, Sixtus is focused on the cultural and socio-institutional context of the Czech lands at the end of the 18th and first half of the 19th century. In particular, he is currently working on the Enlightenment transformation of public space in Prague and Bohemia at the time.