circa 1790, England.
Sources: [1], [2]
This is clearly a portrait of Fath Ali Shah of Qajar, which is seen seated on a throne, wearing a crown, jewelled clothing and a sword. Apparently, Europeans mispronounced his name at the time calling him Fethaly Cham or Fethaly Chah. It seems this portrait is an English copy of an earlier French version called Fethaly Chah Empereur des Persans which can be seen on the second external link seen above.
This Persian Emperor is still a controversial figure in Iran. During his reign, Persia lost her hegemony in Caucasus to the Russian Empire. Also, the an early version of the Lion and Sun emblem is seen as well, in which the lion did not hold a sword.
