Michał Jan Pac (1730-1787) was a Polish nobleman, Lithuanian Marshal of the Bar Confederation from 1769 until 1772, Chamberlain of King August III Sas.He lived in exile in France after the defeat of the Confederation.In 1780, he bought the castle and the landlorship of the village of Marainville in Lorraine; his steward, Adam Weydlich, made acquaintance with the village syndic, François, who had a son, Nicolas, born in 1771.