The OED says:
Many commentators state that
none should take singular agreement, but this has generally been less common than plural agreement, especially between the 17th and 19th centuries... Plural agreement [is] now the commoner usage, the singular being expressed by
no one.
There then follows an excerpt from the Anglo-Saxon Chronicle of 1070:
Beleaf þær nan buton an munec. (None were left there except one monk.)
The use of "none are" goes back a long way!