In what year is the Grand Duchy of Lithuania generally considered to have been officially Christianized under the rule of Jogaila following the Union of Krewo?
Note
Following Jogaila's (Władysław II Jagiełło) conversion to Christianity after the Union of Krewo (1385), the Grand Duchy of Lithuania underwent official Christianization in 1387 when Jogaila as Grand Duke initiated the formal baptism of the population and the establishment of dioceses. This event marked the end of Lithuania's status as the last major pagan polity in Europe and reshaped its religious and political orientation.