Military organization used by the Manchu tribes of Manchuria (now northeastern China) to conquer and control China in the 17th century.
The system was developed by the Manchu leader Nurhachi , who in 1601 organized his warriors into four companies, each known for its banner of a distinguishing colour. More Banners (as the companies were known) were soon established, and, as the Manchus began to conquer their Chinese and Mongol neighbours, they organized their captives into similar companies. With these troops the Manchus conquered China and established the Qing dynasty in 1644. Over time, the Banners' fighting qualities deteriorated, until by the end of the 19th century the system had become largely ineffective.