Lying to the north of Afghanistan, Tajikistan was on the Russian side of the net during the Great Game of the nineteenth century. But there is some evidence that we tried to cause the Russians trouble here when we could.
In the late nineteenth century we were using Afghanistan, which we partly controlled, as our proxy in the area to control Russian expansion southwards. In 1883, allegedly under British influence, the Afghans broke an agreement between us and the Russians of 1873 and invaded part of present-day Tajikistan in the region of Shighnan and Badakhshan. The local Tajiks seem to have preferred Russian rule to Afghan rule and threw the Afghans across the Panja after fighting at Somatash and Yaims.
In the late nineteenth century we helped to ensure that our ally the Emir of Afghanistan got control of a chunk of disputed land in this area to create the so-called Wakhan Corridor, that strange, sticking out, pointy bit at the top right-hand corner of Afghanistan. It’s a narrow piece of land that stretches all the way to China and it served an important purpose. It helped ensure that the British Empire and the Russian Empire didn’t have to share a border here, and it’s there to this day.
Then, after the Russian Revolution, suddenly Russian control of what is now Tajikistan seemed vulnerable. The most effective local opposition to Soviet rule came from local rebels (particularly in the Fergana region of Tajikistan). Some of the Soviets were convinced we must be arming and aiding these rebels.