The Allen in Hopkins & Allen was Charles H. Allen. Hopkins & Allen was formed in 1868 in Norwich, Conn.

Ethan Allen was from Massachusetts. He was born in 1806 and died in 1871.

Firearm firms associated with Ethan Allen, from Wikipedia:
1831–1837: E. Allen (Grafton)
1837–1842: Allen & Thurber (Grafton)
1842–1847: Allen & Thurber (Norwich)
1847–1854: Allen & Thurber (Worcester)
1854–1856: Allen Thurber & Co (Worcester)
1856–1865: Allen & Wheelock (Worcester)
1865–1871: E. Allen & Company (Worcester)

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