I am looking for information about Hubbard Allen (b. Oct 1823, d. 25 May 1895), and thought it interesting that you mentioned the marriage of an Allen and a Hubbard.Perhaps there is some relationship and that is why he has the unusual given name of Hubbard.
Additionally, I believe there is a connection to Chautauqua County, NY for my Allens (Hubbard's grandson, George Washington Allen, married Mary Rebecca Coffin, who was born in Chautauqua County).Since I don't know where Hubbard lived, it seems possible that he lived in Chautauqua as well.But I also have the possiblity of North Carolina as a place of residence... so I don't know.
The info I have is: Hubbard married Emily Amanda Welch (b. Feb 1829, d. 26 Feb 1898, her father is from NC).They had a son, Henry Ervin Allen (b. 20 Jan 1850, d. 19 Apr 1907 WA). Henry married Sarah Elizabeth Cunningham (b. 3 Nov 1853, d.9 Jan 1924 WA).They had six children: George Washington, Ella Lee, Lulu Mary, Samuel Carl, James Iredell, and Walter Scott.