I am familiar with the royal descent of the Gradenigos of Saint Landry. In father Hebert's catholic records, he makes a reference to Jean/Giovanni Gradenigo, the father of Joseph Gradenigo, and the fact that he came from a family of Italien nobles, in which one was a Doge of Venice. They didnt know why he came to America though. Anyway, his son, Joseph started the line of the racial mixed Gradenigo line by three different women of african descent. I come from Henrietta Gradenigo, a free woman of color of Opelousas.
So, I Guess that makes us distant cousins. Yea, I saw some sites where they have the Gradenigo tree to the 17th century, but I havent seen one in which it goes all of the way to the 12th century though. I am still researching my line of Gradenigos.