Allen Upward 
International Spy [EPUB ebook] 

Being the Secret History of the Russo-Japanese War. Excerpt: "I never use the same stratagem more than once. It is to this rule that I attribute my success. On previous missions to Russia I assumed the disguises of a French banker, of the private secretary to Prince Napoleon, of an emissary from an Indian Maharaja, and of an Abyssinian Maduga. I now decided to go thither as an Englishman, or rather-for there is a distinction between the two-as a Little Englander.