Lashio is the largest town in northern Shan State, Myanmar, about 200 kilometres (120 mi) north-east of Mandalay. It is situated on a low mountain spur overlooking the valley of the Yaw River. Loi Leng, the highest mountain of the Shan Hills, is located 45 km (28 mi) to the south-east of Lashio.

The Shan language is the native language of the Shan people and is mostly spoken in Shan State, Myanmar. It is also spoken in pockets in other parts of Myanmar, in Northern Thailand, in Yunnan, in Laos, in Cambodia, in Vietnam and decreasingly in Assam and Meghalaya. Shan is a member of the Tai–Kadai language family and is related to Thai. It has five tones, which do not correspond exactly to Thai tones, plus a sixth tone used for emphasis. The term Shan is also used for related Northwestern Tai languages, and it is called Tai Yai or Tai Long in other Tai languages. Standard Shan, which is also known as Tachileik Shan, is based on the dialect of the city of Tachileik.