John Christian died of pneumonia on 25 December 1639 in Ostróda, six months after his second (morganatic) wife, Anna Hedwig of Sitzsch. Four months later, on 19 April 1640, his body was sent to Brzeg, where he arrived on 1 May. However, the formal funeral took place only less than a year after his death, on 12 December 1640. His body was deposited in the Church of St. Hedwig in Brzeg, alongside his first wife, Dorothea Sybille.
