Leaders--they with commissioners for NE created a treaty and therefore the sagamores are spokespersons or leaders of the tribes.
Sagamores of the tribes were meeting with NE leadership to create a treaty. Only leadership would be recognized for the treaty process. The sagamores were either leaders of the tribes or acting as diplomats to complete the treaty process.
One factor that helped Buddhism spread to China was the way of the Silk Road.
He is trying to find things that interest him, he isn't trying to find things that isn't going to interest him.
( to be honest I don't know hope this helps )
I would say answer number 4
