Yên Bái is a city and urban district in Vietnam

Vietnam

Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...

. It is the capital of the Yen Bai province

Yen Bai Province

Yên Bái is an agricultural-based province located in Tay Bac, the northern part of northern-central Vietnam. It shares borders with five provinces which are Lao Cai province, Lai Chau province, Son La province, Tuyen Quang province, and Phu Tho province...

, in northeastern

Dong Bac

The Northeast is the region at the north of the Red River Delta, Vietnam. Northeast called to distinguish them from the Northwest, but it's actually in the north and northeast of Hanoi, wider than Việt Bắc. The northeast is one of three sub-regions of northern Vietnam...

 Vietnam. As of 2003 the district had a population of 78,016. The district covers an area of 58 km².

On 9 February 1930, part of the 4th Regiment of Tonkinese Rifles

Tonkinese Rifles

The Tonkinese Rifles were a corps of Tonkinese light infantrymen raised in 1884 to support the operations of the Tonkin Expeditionary Corps...

 stationed at mutinied against their French officers in the Yen Bai mutiny

Yen Bai mutiny

The Yên Bái mutiny was an uprising of Vietnamese soldiers in the French colonial army on 10 February 1930 in collaboration with civilian supporters who were members of the Viet Nam Quoc Dan Dang ....

. They were suppressed by loyal troops from the same unit. This incident led to widespread disturbances against French rule across northeastern Vietnam during 1930-31.