P&O stems from a partnership formed in 1822 between Brodie McGhie Willcox, a London shipbroker, and a Shetland-born former Royal Navy clerk named Arthur Anderson who had worked in Willcox's office since 1815.
They built up a business linking Britain and the Iberian Peninsula, owning sailing ships and managing steamers. During the Portuguese and then the Spanish civil wars of the early 1830s, they ran guns, raised loans and chartered steamers as warships and troop carriers for the legitimate heirs to both thrones. Their peacetime cargoes included anything from machinery for minting money to giraffes.
In 1835 they joined with Captain Richard Bourne, a Dublin shipowner, and began a regular service between London, Spain and Portugal under the appropriate name "Peninsular Steam Navigation Company". On August 22, 1837, Bourne signed the first commercial contract for carrying mails by sea, between Falmouth - the established "packet" port - Vigo, Oporto, Lisbon, Cadiz and Gibraltar, and with this financial security laid the traditional foundations of P&O.
Such contracts were to be a major source of the company's revenues until the Second World War.
The ship making the first contract run, the 800-ton Don Juan, was wrecked on her return voyage. Fortunately Anderson, who was aboard, helped save the mails and Peninsular Steam weathered the loss.
Its reputation grew. It was consulted on the extension of similar mail services into the Mediterranean. In1840 it received a contract for a monthly run to Alexandria, and to raise the one million pounds needed became a limited liability company.
The Peninsular and Oriental Steam Navigation Company was incorporated by Royal Charter, and remains to this day one of few British companies not operating under the Companies Acts.
Larger ships were acquired for the Egyptian run, still larger ones - all of 2,000 tons - built to brave monsoon weather on the Calcutta/Suez line opened in 1843. By 1845 P&O services reached Singapore and Hong Kong and in 1852 extended to Sydney.
The company's three great Imperial mail routes - to India, the Far East and Australia - had been established in less than a decade.
As it is the Don Guan that made the first
contracted run for the Peninsular & Oriental Steam Navigation Company, she is thus argueable the first vessel P&O operated as such. Before that the ships did not really operate under that name, as far as I interpret it from the text I found.
But I guess it's open to interpretation, really, as both texts are slightly different.