This was one of the earliest settlements within the Zaria plains. Its antiquity like the Kofar Fada is clearly demonstrated by the fact that it was at one time part of the old Madarkachi settlement. However, following the establishment of the Birni and the royal Palace, the significance of the area, particularly around Madarkachi was drastically reduced. This may be due to the new role the whole area behind the royal Palace came to assume following its construction. According to local tradition the ward derived its name from the existence of a door (Kofa) at the back (Bai) of the Palace, hence the name Kwarbai in reference to that door.
Another tradition claimed that Kwarbai derived its name from a special class of warriors who constituted the members of the royal Mallawa family who resided in the northern part of the ward near the royal Palace. By the beginning of the 19th century, following the Jihad in Zazzau, the population of Kwarbai ward got a tremendous boost after the settlement of Malam Musa the first fulani emir of Zazzau and many members of the Mallawa ruling family and their servants.