|British India Steam Navigation Company East Africa Coast Service. © NMM|
The British India Steam Navigation Company (BISNC) grew out of a trading partnership established in India by William Mackinnon and Robert Mackenzie in 1847. The partners formed the Calcutta and Burmah Steam Navigation Company in 1856 to operate mail services in the Bay of Bengal. The shipping company prospered and soon outgrew its Bay of Bengal home, becoming the British India Steam Navigation Company in 1862. A line to London opened in 1874.
P&O acquired British India in 1914 and, although it retained its identity, domination by P&O grew until BISNC disappeared during the P&O reorganization of 1971. During the first half of the twentieth century, it had the largest fleet under the British flag, whether measured by number of ships or by total tonnage. With the notable exception of its 'home line', its extensive network of routes was exclusively within the Indian Ocean.