The BSU was formed after the accession of four individual princely states to the new Dominion of Pakistan in 1948. The area became the Kalat Division when the Union was dissolved. The first head of the Union was the Khan of Kalat, Ahmad of Kalat. The main governing body was the Council of Rulers which comprised the Khan-e-Azam, the Jam of Las Bela and the Nawabs of Kharan and Makran. Decisions on major issues could be taken by a jirga or council of all the nobles or sardars of the Union.