Here's a fun fact for you

I had an interesting conversation here in Afghanistan the other day with a fellow soldier/fly fisherman. He was asking me if I knew which part of the country the Brown Trout originally came from and even though I had part of the answer for him I was embarrassed not to be able to give him more off the top of my head so here are some Brown Trout facts for the new fly fisherman out there or those who just wish to be informed.

The Brown Trout or Salmo Trutta in Latin is a fish from the Salmonid family. That classification includes both lacustrine or potadromous true freshwater Browns that return from a freshwater lake and the anadromous variety which are those that return from the sea. A lacustrine brown is classified as Salmo trutta morpha lacustris, and an anadromous Brown is classified as Salmo trutta morpha trutta. The classification for a true stream dwelling brown is Salmo trutta morpha fario. This can get confusing because the reasons for why a Brown trout becomes anadromous is unknown and there appears to be no genetic differences between them.
The Brown trout is believed to originate in Europe but there are those who believe that may not be true because of isolated populations believed to be native. Brown trout can and have lived to ages over 20 years old but it is widely held that over 80% of anadromous females more than likely succumb to the strains of spawning.

The original brown trout stocking happened in the Baldwin River in Michigan on April 11, 1884 and other maintain it was the Pere Marquette in 1883. Historians from Wisconson have also claimed they were first stocked in Lake Michigan in 1883 but that the stocking did not take. It is believed that subsequent stockings planted German fish in the Eastern US and Loch Leven Browns, a fish transplanted from Scotland, in the Western US.
Loch Leven Browns can be identified by their coloration. These fish tend to be more silvery than yellow with even spotting, they lack halos and have little to no red. They generally are a closer match to an anadromous brown in their coloration
German Browns on the other hand can be quite  a bit more colorful with a lot more red in the spotting and dull to sometimes bright yellow bellies. Their spotting is more sporadic and they often have distinct halos around their spots especially mid flanks.

References
USGS
Wikipedia
Wisconson DNR