The sunflowers we know today descended from a wildflower in North America that people used for oil and, by grinding the seeds, for flour. They were first cultivated in Mexico. From there, the sunflower was bred to produce more and bigger seeds, and spread all over the Americas.
But the history of the sunflower really took off when it was exported to Europe, and it was in Russia that the flower found its biggest popularity. Read what happened there at Kuriositas. -via the Presurfer
(Image credit: Flickr user Brian Hathcock)