Complex sentence: The castle was bought by her husband for the sum of 900,000 livres in 1700 and had been the residence of Jean-Baptiste Colbert anf his family it had been abandoned by them since their disgrace at court.
Split into simpler sentences: The castle was bought by her husband for the sum of 900,000 livres in 1700 and had been the residence of Jean-Baptiste Colbert and his family. It had been abandoned by them since their disgrace at court.