The Chittagong Hill Tracts, Sylhet, Mymensingh, Barisal and North Bengal regions are home to diverse tribal peoples.

The current TFR in Bangladesh is 1.930 per woman,[16] globally considered to be below the benchmark for replacement level fertility.

At this TFR and without migration, Bangladesh's population is expected to soon reach a stage where it neither grows nor shrinks, once the top of its age pyramid fills in.

[27] Source: UN World Population Prospects[29] The vast majority (about 99%) of Bangladeshis are of the Bengali ethno-linguistic group.

Minority ethnic groups include Meitei, Tripuri, Marma, Tanchangya, Barua, Khasi, Santhals, Chakma, Rakhine, Garo, Biharis, Oraons, and Mundas.

[30][31] In the 1971 independence war many of them sided with Pakistan, as they stood to lose their positions in the upper levels of society.

[32] Refugees International has called them a "neglected and stateless" people as they are denied citizenship by the governments of Bangladesh and Pakistan.

They are of Sino-Tibetan descent and differ markedly in their social customs, religion, language and level of development.

Smaller groups include the Santals in Rajshahi and Dinajpur, and Khasis, Garos, and Khajons in Mymensingh and Sylhet regions.

[37] The refugee crisis originated in the early 1990s when the first wave numbering some 250,000 of the predominantly Muslim ethnic group fled persecution from their home in Rakhaine—Myanmar's westernmost state.

[52] On 28 September 2018, at the 73rd United Nations General Assembly, Bangladeshi Prime Minister Sheikh Hasina said there are 1.1-1.3 million Rohingya refugees now in Bangladesh.