Kertész is not too frequent surname in Hungary, but, according to Census of taxpayers, taken in 1715 there were recorded Kerészes in twenty various places. I can inform you only about Kertészes in Central Hungary, Dunaegyháza, Apostag and Ráckeve. János Kertész (in firs record Kerti¹) was born in Dunaegyháza in 1720 and died in Apostag in 1774. His (and his wife's Mária Pálenkás) daughter Erzsébet (b.1764) married Péter Szekér and moved into Ráckeve. Their daughter Erzsébet married János Takács in Apostag, she was my father's great-grandmother.