Complex sentence: This marriage was one of three Franco-Spanish alliances negotiated with the Duke of Orléans, Regent of France between 1715 and 1723 during the minority of Louis XV of France.
Split into simpler sentences: This marriage was one of three Franco-Spanish alliances which had been negotiated with the Duke of Orléans. The Duke of Orléans was the Regent of France in the Regency of 1715-1723 during the minority of Louis XV of France.