Bengal region: West Bengal and Bangladesh Largest City Kolkata [ 1 ] 23°25′N 90°13′E ﻿ / ﻿ 23.42°N 90.22°E ﻿ / 23.42; 90.22 Main language Bengali Area 232,752 km² Population (2001) 209,468,404 [ 2 ] [ 3 ] Density 951.3/km² [ 2 ] [ 3 ] Infant mortality rate 55.91 per