Jayavarman IV, who reigned from 928 to 941, divided the Khmer kingdom by establishing a new capital in the remote location of Chok Gargyar ("Island of Glory", present-day Koh Ker), just east of the southern tip of Phnom Kulen.* It has been suggested that Jayavarman IV was a usurper to the Khmer throne, but there is no clear evidence of this. However, it is certain that he wielded a great deal of military power. (Inscriptions reveal that he ruled over the territories of Battamabang, Siemreap, Kampong Thom, Kampong Cham, and Ta Kev.) Called 'Lingapura' in inscriptions, this royal ceremonial complex was built on a grand scale and originally contained some of the largest sculpture ever created by the Khmer. Not surprisingly, over the centuries most of the sculpture has been looted or moved to museums. Some of these pieces are on view at the Angkor National Museum in Siem Reap. Although Koh Ker's most prominent feature is the great pyramid, Prasat Thom, there are some intriguing outlying ruins as well, including Prasat Neang Khmau and root-covered Prasat Pram.
*The Khmer capital was moved from Chok Gargyar back to Angkor by Jayavarman IV's successor, Harshavarman II (reigned 941-944).