Complex sentence: Lydia joined the Lynn Female Anti-slavery Society when she was sixteen; in the controversies which divided the abolitionist movement during the 1840s Lydia would support the feminist and moral suasion positions of Nathaniel P. Rogers.
Split into simpler sentences: Lydia joined the Lynn Female Anti-slavery Society when she was sixteen. In the controversies which divided the abolitionist movement during the 1840s, Lydia would support the feminist and moral suasion positions of Nathaniel P. Rogers.