Who first thought they had encountered the ten "lost tribes"?

If you can write the answer in a sentence that would great.

1. Go to http://www.google.com

2. Type ten lost tribes

3. Press the Enter key.

4. Read, read, read.

If you want someone to check over the sentence YOU write, please post it here.

I am trying to find the answer to this too does anyone know

The first person who claimed to have encountered the ten "lost tribes" is Benjamin of Tudela, a Jewish traveler from the 12th century.