sentences:  Ferdinand Charles first married Anna Isabella Gonzaga (d. 11 August 1703), daughter of Ferrante III Gonzaga, sovereign Duke of Guastalla.This marriage was arranged by the assistance of his aunt, empress dowager Eleanor Gonzaga, and took place in 1671.Anna Isabella Gonzaga was the heir of the Duchy of Guastalla and Luzzara, and her rights transferred these areas, which had long been a source of conflict between the two Gonzaga lines, to the Mantua line of the Gonzaga dynasty.