Just 'fluffing the Author's feathers' here Ben. But I'm sure 'trappers, et. al.' were eating them long before that. There name for Rainbow's was 'dinner.'
But the presumption of the most transplanted fish in the world (time wise) I have no doubt. Will have to go back to Google, but I'm fairly (well more than a bit off from memory) but the "Rainbow/Steelhead" were nailed down back in the late 1700's. Russia?
Edit: Well close anyway from a dusty memory.
"The species was originally named by Johann Julius Walbaum in 1792 based on type specimens from Kamchatka. Richardson named a specimen of this species Salmo gairdneri in 1836, and in 1855, W. P. Gibbons found a population and named it Salmo iridia, later corrected to Salmo irideus, however these names faded once it was determined that Walbaum's type description was conspecific and therefore had precedence (see e.g. Behnke, 1966).[5] More recently, DNA studies showed rainbow trout are genetically closer to Pacific salmon (Onchorhynchus species) than to brown trout (Salmo trutta) or Atlantic Salmon (Salmo salar), so the genus was changed.
Unlike the species' former name's epithet iridia (Latin: rainbow), the specific epithet mykiss derives from the local Kamchatkan name 'mykizha'; all of Walbaum's species names were based on Kamchatkan local names.
The ocean going (anadromous) form (including tho..... " Etc., and etc.
fae