I heard of a Delaware trade jargon for that area where the Lenape lived, back east in colonial times. Used for trade between Lenape and europeans. Simplified Lenape Language to make understanding easier. In other eastern areas other Languages probably have been use too. In the Northwest there was a Chinook jargon. For southern Plains, I guess, Comanche was used often as Lingua franca. Also at treaties, like Medicine Lodge Creek, Comanche was a main Language I think to recall. Sign Language was known in the whole Plains area.