Complex sentence: The reasons are that the church was destroyed by the Swedes during the Swedish occupation of Novgorod in 1611-1617, so Euphrosyne the abbess visits Moscow in 1618 to ask Michael I of Russia for funding.
Split into simpler sentences: The reasons are that the church was destroyed by the Swedes during the Swedish occupation of Novgorod in 1611-1617. As a result, Euphrosyne the abbess visited Moscow in 1618 to ask Michael I of Russia for funding.