en.wikipedia.orgII think Betsy Ross made the first American Flag. I think this because how else would the story of her began. I think there may have been a dairy or journal of hers that was not found.  There may have also been a journal of the men like George Washington that may have documented something. Betsy Ross was most likely to be the one that did it,I mean seamstress most likely did it. That is my opinion on who made the first American Flag.