John Middleton & Co. described itself in 1894 as an "export business in tea, silk, etc. to the U. S." Although it was an American company, most of the business was conducted through their office in Yokahama, Japan. By 1900 they were involved in supplying American-made machinery and heavy equipment to customers in Japan and China

Most of the letters in the collection were written by George W. Middleton, who was evidently in charge of the Yokahama office and perhaps president of the company, which by 1900 was known as Middleton & Smith. Many of their transactions went through institutions like the Chartered Bank of India & China, the Hong Kong & Shanghai Dist. Corp., and the Russ-Chinese Bank.

The Records of John Middleton & Company present an important look at American business participating in the economic and political expansion into the Far East by the major nations of the world during the latter years of the 19th century.