A cistercian monastery was founded near here in the year 1142. One of the principal tasks of the monks was the cultivation of the grounds and lands around the monastery. In 1278 King Otakar II of Bohemia sent Henry, the abbot of Sedlec , on a diplomatic mission to the Holy Land. When leaving Jerusalem Henry took with him a handful of earth from Golgotha which he sprinkled over the cemetery of Sedlec monastery, consequently the cemetery became famous, not only in Bohemia but also throughout Central Europe and many wealthy people desired to be buried here.The burial ground was enlarged during the epidemics of plague in the 14 th century (e.g.in 1318 about 30 000 people were buried here) and also during the Hussite wars in first quarter of the 15 th. century.
After 1400 one of the abbots had a church of All -Saints erected in Gothic style in the middle of the cemetery and under it a chapel destined for the deposition of bones from abolished graves, a task which was begun by a half blind Cistercian monk after the year 1511. The charnel-house was remodelled in Czech Baroque style between 1703 - I710 by the famous Czech architect, of the Italian origin ,Jan Blažej SANTIM-Aichl. The present arrangement of the bones dates from 1870 and is the work of a Czech wood-carver, František RINT (you can see his name, put together from bones, on the right-hand wall over the last bench).
Our ossuary contains the remains of about 40 000 people. The largest collections of bones are arranged in the form of bells in the four corners of the chapel.
The most interesting creations by Master Rint are the chandelier in the centre of the nave, containing all the bones of the human body , two monstrances beside the main altar and the coat-of arms of the Schwarzenberg noble family on the left-hand side of the chapel.