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When did Lithuania officially adopt Roman Christianity?

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Map showing Poland's territory in 1634 under the reign of Wladyslaw IV Vasa, shaded in pink and spanning from the Baltic Sea in the north to near Kyiv in the southeast. Major present-day cities such as Warsaw, Krakow, Gdansk, Vilnius, Minsk, Lwow (Lviv), Pinsk, and Kyiv are marked within the territory, with surrounding cities like Moscow, Riga, Vienna, and Budapest shown for reference. — Polish-Lithuanian Commonwealth Poland's territory in 1634, during the reign of Władysław IV Vasa.

Lithuania officially adopted Roman Christianity in 1387, when the Grand Duke Jogaila formally introduced the faith to his Lithuanian-speaking subjects following his agreement to unite with Poland.12

While the chieftain Mindaugas had accepted Roman Christianity in 1251 and was crowned in 1253, he was assassinated ten years later, and the population subsequently reverted to traditional paganism. Consequently, the 1387 conversion under Jogaila is recognized as the definitive official adoption of the religion for the state.312