It is usually performed by singers from France, Canada, Belgium, Switzerland, or any of the other francophone areas of the world.
Eventually the early French pop music and the chanson styles crossed over and combined.
Radio stations in France are required to play at least 40% of their songs in French, during prime hours.
France's Pelchat amendment to the 1994 Broadcasting Reform Act is the law which requires this.
[1] A list of Francophone pop music artists and the decades when they rose to prominence.