Complex sentence: Standish led ten men of Plymouth in arms to rescue Squanto from Corbitant, and assaulted the Wampanoag village at Nemasket, but by that time Corbitant had released Squanto and withdrawn from the area.
Split into simpler sentences: Standish led ten men of Plymouth in arms to rescue Squanto from Corbitant. They attacked the Wampanoag village at Nemasket, but by that time Corbitant had released Squanto and withdrawn from the area.