As with the other colonial powers smuggling opium into China, bribing corrupt officials, and generally making a mockery of Chinese sovereignty during the 19th and early 20th centuries, Great Britain maintained "spheres of influence" within China, and maintained post offices there and in Hong Kong. This understandably led to some resentment among the Chinese who attempted to forcibly eject the foreign parasites. The Boxer Rebellion (1898-1901) was crushed by the multinational China Expeditionary Force, to which the various colonial powers had contributed personnel. In a truly British combination of efficiency and irony, Great Britain added Indian units to the C.E.F., thereby setting one colonized and exploited people against another.
In 1904, a set of nine Indian stamps from its Edward VII Issue were overprinted for use by the C.E.F. (Scott #M12-20). 5,568 sets were sold, and Scott '12 prices the unused set at $118.00.
The set has potential appeal in three growing markets: collectors of British Commonwealth, India, and China. Many of the best investments in Indian stamps are to be found among the obscure colonial back-of-book items and the Convention States. The Indian stamp market is really just beginning to take off, and is at a stage similar to the Chinese stamp market of 30 years ago.
The set should also do well based upon demand from China, but that may require a change in attitude on the part of Chinese collectors. Many, if not all, of the better foreign offices in China stamps are grossly undervalued, because most Chinese collectors disdain them as relics of foreign imperialism, which they are. Nevertheless, I feel that they are excellent investments solely on the basis of growing demand in their home countries, and because I believe that eventually, the Chinese will bid them up as well. Many of these issues are undervalued to such an extent that they are currently selling for less than P.R.C. souvenir sheets and Cultural Revolution sets which are at least 30 to 100 times more common. When reticence begins to replace rage, they will zoom upward at a rate that will shock and amaze the the vast majority of collectors who unwisely neglected to read this blog.