Source: TW
The lama tAranAtha gives a curious tale regarding the bauddhAchArya asaNga from puruShapura. He says that during his time, there was a settlement of a force of Qarluq Turks (!!) near the “non-bauddha” city of ayodhyA. The Qarluqs are said to have attacked him and his disciples when he was giving a sermon. He asked them to remain in meditation, and the Qarluq arrows are said to have “turned to dust”. When they struck asaNga with a sword it broke into a hundred pieces. Seeing them immune and unmoved the Qarluqs “bowed down in great reverence and went away.”
The curious point is that most historians agree that asaNga flourished around 400 CE. That is too early for the Turkic Khaghanate, let alone the independent Qarluq confederation within it. Hence, either tAranAtha was projecting a much later event to the time of asaNga, or he simply meant some other group.
Tibetan translators have sometimes rendered the Sanskrit turuShka as Qarluq, as they were one of the most familiar Turks. However, asa~Nga was before there were any turuShka-s on the Indian horizon, let alone having a colony in ayodhyA.
Hence, one possibility is that he was talking of a Hunnic colony and conflated them with the turuShka-s. But a Hunnic colony in ayodhyA at the zenith of gupta power seems unusual, if true. Were there Hun mercenaries in India even before their invasions?