The story of tenkara in the United States is much older than ten years.
In 1990, Yuzo Sebata, a humble Japanese tenkara fisherman visited the United States and introduced tenkara to the famous western rivers. His introduction was documented by putting together a video of his visit. The Toshiba EMI Fishing Video, "The Yellowstone Series" follows Sebata san while fishing tenkara in America for the first time on a professional scale. The video was available for purchase in 1991. At that time, his visit was two weeks of filming and two weeks of touring the area fly shops and meeting with many local anglers to spread the word of tenkara.
The credits in the film are of many American fly fishermen. A 20 year Montana fly fishing professor has a cameo in the film stating Sebata sans full flexing rod would be a lot of fun with the average three pound rainbow trout. Sebata san is also seen in more than one river fishing together with children and other fly fishermen. He caught fish where ever he went and his famous sugegasa (traditional Japanese conical hat) with a few of his flys kept underneath was shown in the film.
If you have a chance to purchase the VHS film, or even watch it, I highly recommend it. I also urge you to explore the fishing of Sebata san. In your search, you will find his recipe of living in the mountains with many tips for your own mountain backpacking trips.
Yuzo Sebata is a living tenkara legend. His reputation in Japan goes deeper than tenkara, he is known as a hard core mountain enthusiast that also lives off the land. Often in his time, Sebata san would live of the land for weeks eating sansai, mushrooms and of course, iwana (trout) that he caught in the mountain streams.
While Sebata san visited local area fly shops and fishing museums, you can see from the picture here that there is a section on Japanese tenkara on display.
I believe it is important to understand that tenkara is an old form of Japanese style fly fishing. There are many masters and tenkara enthusiasts from Japan that have been teaching tenkara to the masses long before commercial vendors outside of the country of origin.
Sebata san is prominently included in many books by Soseki Yamamoto from the earliest books on the subject throughout his career.
Tenkara USA has information on Sebata san.
Discover Tenkara works with Sebata san to spread the word of his tenkara knowledge.
Sebata san is also an accomplished fly fisherman and has written many books on the subjects of fly fishing, tenkara and foraging in the mountains.
I have interviewed Sebata san and was invited to meet and stay with him by Keiichi Okushi. I was his guest at his summer residence at the Tadami Bansho.
I think it is important to keep in mind that tenkara was introduced to America in 1990.