the Khanate of Bukhara (q.v.) established one of the three foreign post offices operating in late 19th century Afghanistan (the other two being those of British India and the British Army). The postal agency was located in Mazar Province, and acted as a transfer point for large amounts of commercial mail generated between Bukhara and the other trans-Oxus (now Amu Dar’ya) River khanate regions in central and W Asia, ranging from the Pamirs plateau to the Aral Sea. The trans-Oxus khanates were relegated to protectorates of Imperial Russia status during the 1870s-1880s; Bukhara retained limited independence, and was not considered as being part of the Russian Post Office. The Bukhara Postal Agency used the stamps of Afghanistan and appropriately inscribed Afghan postal markings; the agency appears to have been in operation as late as early 1922, at which time the Bukhara Republic joined the U.S.S.R.