1226 massacre in Georgia
Source (Wikipedia): Hundred Thousand Martyrs of Tbilisi

The Hundred Thousand Martyrs are saints of the Georgian Orthodox Church, who were put to death, according to the 14th-century anonymous Georgian Chronicle of a Hundred Years, for not renouncing Christianity by the Khwarazmian sultan Jalal al-Din upon his capture of the Georgian capital of Tbilisi in 1226. The source claims the number of those killed were 100,000. The Georgian church commemorates them on 13 November.