Cape Breton Island (French: Île du Cap-Breton, formerly Île-Royale; Scottish Gaelic: Ceap Breatainn or Eilean Cheap Breatainn; Mi''kmaq: Unamaꞌki) is an island on the Atlantic coast of North America and part of the province of Nova Scotia, Canada. The 10,311 km 2 (3,981 sq mi) island accounts for 18.7% of Nova Scotia''s total area.