The Petun, also known as the Tobacco people or Tionontati, were an indigenous Iroquoian people of the woodlands of eastern North America. Their last known traditional homeland was south of Lake Huron's Georgian Bay, in what is today's Canadian province of Ontario.

Georgian Bay is a large bay of Lake Huron, in the Laurentia bioregion. It is located entirely within the borders of Ontario, Canada. The main body of the bay lies east of the Bruce Peninsula and Manitoulin Island. To its northwest is the North Channel.