The Pied Piper of Hamelin

So, all of us knows the story of the Pied Piper.If not, maybe most of us or you may already heard it from your friends or other people. The story is about a town,called Hamelin,which is plagued by many rats. Then a man came who is a piper who wore a dress of all colors. The town ask the piper to send the rats away exchange of a big amount of money. The piper agreed and drove away the rats but when the piper returned for the money the people won't give him the money so he got mad and drove the children away to a cave.When the townspeople agreed to give the money he sent the children back. But in other version of the story it is more gruesome and  some scholars said that there are connotations of pedophilia.Another version is about the Piper leading the children to the river Weser in which caused them to drown except for a lame boy who couldn't keep up. Others say that he led them to Koppelberg Hill which he took them to a beautiful land away from the cruelty of adults. Another is about when the piper led the children to a cave which is  directly going to Transylvania. Many theories was told and the truth is still not known. But Martin Humberg, a Hamelin historian states that there where once a window thata has an old figure of a man dressed in various colored clothes with children around him.The inscriptiion of the window reads:
 
In the year of 1284, on John's and Paul's day
was the 26th of June.
By a piper, dressed in all kind of colors,
130 children born in Hamelin were seduced
and lost at the calvarie near the koppen.

So there is a big mystery about this Pied Piper. Who is he? Where did he came from? What happened to the children? Maybe some further research may answer these questions.