Kissing appeared in Italy in the15th century. At that time, women were forbidden to drink in Italy. In order to check whether the wife is well behaved, husbands kiss their wives every time they come back from going out. This shows how much discrimination women have suffered in this behavior. Today, the meaning of this behavior has changed in essence.
Of course, kissing may have appeared earlier as a part of sexual behavior, but it did spread widely in Italy in the15th century.