A census search in each year got me Matt Grass in 1880, and Matthew Delherbe in the rest. In the Civil War records I found a Jules Delherbe. Wow, finally a new Delherbe other than the children of Matt! Fortunately I was able to ask my great aunt if she knew this name. She said that was her great uncle.
I tried tracing Jules Delherbe through the war records. (Thanks to footnote, what is now fold3.) His record shows him as being born in New Jersey. He was captured, and he then traded sides to the Union. During this time he used the name Jules Moulin. I thought this strange.... I did a search for Moulin in the New Orleans census and came up with one main family, and another small one in the 1860 census. Jules was able to escape and returned to his troop and once again used the name Delherbe. He is listed as one of the French who possibly used place names as a surname during the Civil War or as using his mother's name which was common.
The Moulin name kept nagging at me. So I ordered Jules marriage certificate from Baton Rouge. On it he gave the names of his parents as Charles and Marie Delherbe. This happened to be the names of the Moulin family I found living in New Orleans in 1860. Charles and Marie Moulin living with son, Jules, Mathurin, and Charles. All the same ages as my Jules and Mathurin (Matt) Delherbe. I then notice that in the 1880 census Matt is living a few houses down from Charles and Marie Moulin.
I then ordered Charles and Marie Moulin's marriage certificate. Marie's maiden name was Delherbe. So mystery solved, my families name was Moulin, changed to DeL'herbe or Delherbe.
After some more digging, I found that apparently Marie was arrested and brought to trial for stealing money by making a claim to be the mother of a one Charles Redcoat after the Civil War. She took his government pension, and was later caught. So perhaps this is why after 1870 even Matt used his mother's maiden name instead of Moulin.
Marie DeL'Herbe had come to New Jersey from France in 1830, her brother Peter Delherbe and her mother stayed in New Jersey and another brother, Francois Delherbe went on to Georgia, his son Achille apparently went back to France.
I now have been able to trace the DeL'Herbe name back to France and find the ancestor's that lived there. I have also luckily through my website, as well as other works, have found many lost cousins who we did not know existed with Delherbe family ties. Thanks to the search engines :) my last fifteen years of research and queries made it easy for cousins looking for their family ties to find me!
I would like to add that there is a branch of the family living in Chile that may be related. I have become friends with one such Delherbe who was born in Chile and now resides in Florida. So, if you are a Delherbe from Chile and are reading this. Please feel free to comment and add any information to our family tree that you would like to share. Thanks!