At the start of Book One of the Antiochene Wars, just after a prologue describing a locust invasion usually dated to 1114 CE, Walter the Chancellor wrote an eyewitness account of an earthquake that struck the Principality of Antioch while he was presumably living there. He described the collapse of walls, towers, and buildings, as well as casualties. Reports also came from Marash, which he said was entirely destroyed, and from Mamistra. He wonders if al-Atharib was also damaged. Residents were said to have slept afterward in tents set up in streets, gardens, squares, thickets, and open plains because of continuing aftershocks (each day, the earthquake threatened for hopeless hours). Later in his text, Walter mentions five months of continuing tremors. Walter dates the earthquake to the night of 29 November 1115 CE, though other sources place it on 29 November 1114 CE. His translators Asbridge and Edgington (2019:80 n.24) date the event to 29 November 1114 CE, as does Ambraseys (2009). Guidoboni and Comastri (2005) date it instead to 29 November 1115 CE. The day of the week was not given, which would have allowed a firm distinction between 1114 and 1115. However, since Walter places the earthquake before the Battle of Tell Danish on 15 September 1115, it appears that either he or a copyist erred with the 1115 dating, and the event should be assigned to 1114 CE. Walter also notes that the town of Mamistra was previously ruined with its citizens and the greater part of the town on the Feast of Saint Brice (13 November).