Book about an adventurer

Question

Several years back I read a book about some kind of adventurer. Not the typical one, since he did not really plan to have all those experiences. The stages I present below are in some random-ish order, not necessarily in the order presented in the book.

He was imprisoned on an island. The habit was that the prisoners who died were thrown into the sea / ocean, where the sharks were already waiting to eat them.

He lived with some native Americans ("Indians"). He got a wife, and then a second wife (the sister of the first wife. They both gave him children (not 100% sure about this, maybe only one had a child with him).

He spent some time into a leper's colony.

He spent some time in a "colony" on some mountain. I remember that here there was a business about faking a special kind of rare butterfly, in order to make some money.

There were some other adventures.

In the end, he breaks the law in some way that that there is no win for him. He decides to move to a country which does not extradite people (I think Panama, not sure though).

Answer 1

It is "Papillon" by Henri Charrière.

After a brief stay at a prison in Caen, Papillon was put aboard a vessel bound for South America, where he learned about the brutal life that prisoners endured at the prison colony. Violence and murders were common among the convicts. [...] They planned to use a sailboat acquired with the help of the associated leper colony at Pigeon Island (Saint Lucia). [...] Papillon entered the Guajira peninsula, a region dominated by Amerindians. He was assimilated into a coastal village whose specialty was pearl diving. There he married two teenage sisters and impregnated both. [...] Papillon was eventually released. He gained Venezuelan citizenship and celebrity status a few years later.

Actually, you remembered quite a lot to be able to find it using Google search. I found it by searching for book island prison leper indians butterfly.