Butler was the son of U.S. Attorney-General Benjamin Franklin Butler and the father of William Allen Butler Jr. All three were leading figures in the New York legal community. In addition to his writings on legal topics, William Sr. wrote fiction, history, and humour both in poetry and in prose.[1] He was a founding member of the Association of the Bar of the City of New York.[2] [1]: http://books.google.ca/books?id=wZczV8ZxgL4C&lpg=PA66&pg=PA65 in American National Biography [2]: https://archive.org/stream/memorialofwillia00holt memorial .