This Vietnamese folklore about Betel leaves has been my favorite for quite a while since childhood. I came across this today on
this site (.pdf file).
A folk-tale of a mythical king relates the origin of betel chewing in Vietnam.
Twin brothers, Tan and Lang, fall in love with the same beautiful girl. Since they are devoted to each other, one of them agrees to let the other marry her. Then, one day, the wife accidentally touches the hand of her brother-in-law which angers her husband.
The brother-in-law is so distressed over the incident that he runs away. When he reaches the bank of a stream he dies of grief and the gods turn his body into a white limestone rock, symbolizing his devotion.
The husband is upset at the absence of his twin brother and goes to look for him. When he reaches the stream he sees the fate of his brother. He is so grieved that he dies in the same place and turns into an areca palm.
Finally, the bride goes to look for the two brothers. When she reaches theriver bank she meets the same fate and turns into a betel vine which grows beside the rock and entwines itself around the palm tree. In spite of a drought, the palm and vine remain green.
The king hears of this and orders them to be brought to him. He places both in his mouth and is engulfed by a feeling of well-being. Ever since, betel has been chewed in Vietnam.
