There are several versions of Zvonimir's death. The 13th century chronicler Thomas the Archdeacon and a charter of king Stephen II, said to have been issued closely after his death in 1089, both assert that Zvonimir died of natural causes. This view had been mostly accepted in modern historiography. Various later sources give the date 20 April of the year 1089 as the date of his death. They also name the village of Kosovo (today's Biskupija near Knin) and the place by the basilica of Saint Cecillia as the place of death. These sources were typically associated with the allegations of his assassination, now believed to be a medieval legend.