Thanks for the great question.
While they really are the same thing, some companies have tranformed them into two different teas. Russian Caravan has become a blend of a few teas (usually a mix of Lapsang Souchong and Keemun), but this was undoubtedly not the original form. The name "Russian Caravan" refers to the long, overland journey that tea would travel on from China to the markets in Moscow. Chests of tea would travel on camelback, often taking a year to complete the journey. Russian-bound tea was famous for the smell of the many campfires it would absorb along the way.
Supposedly, though, the smoking process was already discovered by the Chinese and called Lapsang Souchong. According to legend, an Ancient Chinese teamaker was late to the market one day, so he lit some pine wood to hasten the drying of the freshly plucked leaves. Not only did the tea reach the market in time, but the smoked pine flavor created a sensation!
Here is our Lapsang Souchong
(or Eroica Caravan
-- whichever you prefer!) if you'd like to have a taste of this historially rich, but oft confused, smoky tea.
Your favorite Ancient Chinese teamaker,