Since a variety registration system was introduced in Hungary in 1914, all the necessary information about varieties improved by professional breeders is made public. However, little is known about the origin of varieties bred by local farmers for their own purposes in Eastern Central Europe. The catalogue of the First National Maize Exhibition, held in Budapest in 1914, provides a unique opportunity to investigate the genetic background of the maize varieties of the time. It seems likely that the diversity of this genetic background was preserved until the beginning of hybrid maize breeding. The flint varieties of the time proved to be the most variable (Caribbean, Andean, Paduan and Northern flints). Among the Corn Belt Dents, Leaming, Queen of the Prairie, Reid Yellow Dent, Iowa Goldmine and Northwestern Dent were the most frequent varieties, while Tuxpan, Gourdseed, Shoepeg, Hickory King and Southern Prolific were the most frequent of the Southern Dent varieties. In many cases the varieties introduced into Eastern Central Europe mixed and crossed spontaneously. In addition to professional breeders, many farmers also used the available varieties as components in crosses, in order to develop new varieties. The most popular were dent × flint crosses, using roughly equal proportions of Old Hungarian Yellow Flints of the Caribbean type and early hard-grained flints of the Andean type. Flint × flint crosses were also popular, partly due to the use of maize for human consumption, and partly to the great genetic variability exhibited by flint varieties. Locally developed maize varieties, which have a background quite different from those developed in the North American Corn Belt, could, after suitable breeding, enrich the available sources of heterosis. Further research will be required to determine which of them are the most valuable.