Dharma is essentially the goal of a follower of Buddhism or Hinduism. Dharma is affected by karma which are the tasks that people do in order to get to dharma or, their higher happiness. Rulers and upper Varnas could use this to encourage peace in their society, because all the civilians would be focused on doing good deeds, to have good karma, in order to reach dharma.
Diseases. To list some would be influenza, smallpox, etc.
delegates in Philadelphia to write a new constitution
