The date of the attack on Sinope and the ensuing siege of Trebizond can be determined from three sources: John Lazaropoulos, Michael Panaretos, and Ali ibn al-Athir. John Lazaropoulos dates these events to the Byzantine year of the world 6371, in the second year of the reign of Andronikos I Gidos;[11] the Byzantine year started on the first day of September and ended on the last day of August, and because Alexios I died 1 February 1222, it is clear the second year of the reign of Andronikos began in February 1223, Lazaropoulos' dating points to some time between February 1223 and September of the same year. The chronicle of Michael Panaretos uses exactly the same words to date the defeat of Melik,[2] so we can be assured the siege also fell within this time period.