1847: Ship your ictas to W.H. Davis, Esq. of this place
I was saying the other day how ictas (“things, belongings, paraphernalia”) was among the first Chinook Jargon words to enter regional English.
In terms of there even existing a community of speakers that could have its own local linguistic norms, here’s an extremely early point of evidence:

It’s on a page of an Oregon paper telling pre-statehood Californian settlers’ advice about how to head south to live there. (Go read — it’s amazing firsthand history.)
The writer — notorious Californian C.E. “The Philosopher” Picket of San Francisco — closes his letter with the advice,
Ship
your ictas to W.H. Davis, Esq. of this place,
who will see to their safe landing and stor-
age.
— Oregon City Oregon Spectator, April 29, 1847, page 1, column 1
Local readers understood.
