Jus Soli
Citizenship is acquired at birth when the identity and/or nationality of the parents is unknown. In this regard, the child is assumed to be born to Bangladeshi national(s), and hence, given citizenship upon birth. Jus soli citizenship is also conferred upon Urdu-speaking people of Bangladesh in May 2008 by a High Court verdict (see below).
Read more about this topic: Bangladeshi Nationality Law, Citizenship