Sometimes decisions about how to use one word Indian names is difficult. When the names are hyphenated, such as the Seneca name, Dah-gis-wus-heh, I don’t use the name. Chances of someone finding this name as an English name are pretty small.
However, names like Atteanis are somewhat different. It’s not an English or European looking name, but still, it’s one word and I’ve seen several instances where one person is listed by a word like this, and another from the same location is listed with it as a surname. A good example is a patriot in Maine who served by the name of Ambroice/Ambroise, and another was Frank Ambroise who served. With a one word name that is fairly easy to pronounce, it’s easy to anglicize it by giving the person a European first name.
It’s nice however, sometimes to find confirmation of the decision. One of the interesting aspects of this project is that as I build the file, which is well over 1000 pages now, I add to each surname. So in this case, I was able to see that I had an entry for a very similar surname, also in Maine, in WWI.
Here are the entries:
Attean/Attian
WWI Draft Registration Cards – 1917-1918 – registered as Indian
In Penobscot Co., Maine
- Leonard Weld Attean b 1899
- Joseph Stanley Attian b 1895 Maine
Atteanis
Atteanis, Penobscot Indian
Forgotten Patriots: African-American and American Indian Patriots in the Revolutionary War
http://www.dar.org/library/publications/Forgotten_Patriots_ISBN-978-1-892237-10-1.pdf
Presuming this is the same family, I have to wonder if the men who registered for the draft in 1917 knew that they had an ancestor who volunteered and served in the Revolutionary War, some 135+ years earlier.
Native Heritage Project 
I would be willing to say that they very probably did know their ancestors were in the war.
Indian history was passed down sometimes nightly around the camp fire and other times it was a weekly event, children had to learn the stories to be able to pass them down to future generations as adults.
Ah, the problems with Abenaki names !!!!!! You have just hit the tip of the iceberg in this post.
Attean = French Baptismal name of Etienne (English Stephen)
So you do have a European given name but it has become Indian-ized in pronunciation and in usage.
The first in the line might be known only as Attean, the son perhaps Sosep Attean (Joseph, son of Stephen), and his son might be Soc Sosep Atttean (Jacques, son of Joseph Attean) and so forth. But there are no rules to this game so you can’t count on anything except frustration when you try to sort them all out. If your interested you can read more here
http://www.nedoba.org/gene_names.html
Atteanis = the ending “sis” is like saying junior or the younger one
You might also be interested in my list of the Wabanaki men that served during the Revolution (with interpretation of some of the names) here
http://www.nedoba.org/ne-do-ba/war_rw01.html
Another wonderful resource. I’ll use your list of Rev War soldiers. Thank you so much.
Fascinating