The Orient Steam Navigation Company, also known as the Orient Line, was a British shipping company with roots going back to the late eighteenth century. From the early twentieth century onwards an association began with P&O that eventually culminated in the Orient Line being totally absorbed into that company in the 1960s.

The Beginnings (1797 – 1900):

The Orient Line's beginnings can be traced back to the formation of a shipbroking company by James Thomson in 1797. The company was operating a small fleet of sailing ships by the early 1800s, and by the middle of the century they were sailing on routes all over the world. In 1828 Thomson was joined by James Anderson, and the company was renamed Anderson, Thomson and Company in 1863. The inauguration of a liner service to Australia with the packet Orient in 1866 saw the company renamed Orient Line of Packets, regularly shortened to Orient Line. The transition to steam saw another name change in 1878- the Orient Steam Navigation Company.

Early Twentieth Century (1900 – 1919):

The association with P&O began at the turn of the twentieth century with the two companies sharing an Australian Government mail contract. Each company had a vessel sailing from England to Australia every two weeks, resulting in a weekly service of fast mail ships. This was at a time of rapid expansion for the Orient Line, with a succession of larger ships being built. All had names starting with 'O', such as Otway, Osterley, Orsova, Otranto and Orvieto- a quintet of 12,000 ton ships entering into service in 1909. The First World War saw all of the company's ships commandeered for war service, with inevitable losses. Those that survived returned to the England- Australia service in 1919.

Between the Wars (1919 – 1940):

It was during the last year of the war that P&O strengthened its interest in its partner to gain a majority 51% shareholding, although they continued to operate as separate entities until the 1960's. The Orient Line fleet was upgraded following the war with the purchase of second hand former German vessels from the British Government, made available through war reparations. More new ships were acquired in the second half of the 1920s, most built at Vickers Armstrong Ltd in Barrow in Furness. The company managed to trade through the depression and returned to profitability and new ship building in the mid 1930s.

Second World War and After (1940 – 1960):

The Second World War again saw the requisitioning of Orient Line ships, with all eight seeing service. Unfortunately four were lost, with the other four returning to the England- Australia mail service in 1947. It took a number of years for the company's fleet to be returned to full strength due to the slow industrial recovery after the war. Three new ships of 28000- 29,000 tons entered service between 1948 and 1954; the Oronsay, Orcades and Orsova.

All had increased speeds that allowed them to reduce the sailing time from England to Australia by eight days to 28 days. However, the 1950s also saw air travel beginning to eat into shipping companies' passenger trade. Ships were increasingly diverted to cruising for part of the year, and the Oronsay began a trans-Pacific service in 1954. Despite this downturn in liner traffic, both P&O and Orient Line ordered new, larger vessels- the Canberra for the former, the Oriana for the latter. These ships were the largest and fastest ever for the England- Australia route, with the Oriana reducing the voyage time from 28 days to 21 days due to her top speed of 30 knots. The career as liners for both ships was short lived though, with full time cruising undertaken from 1974 onwards.

The Final Years (1960 – 2005):

The Oriana was the last ship ordered for the Orient Line, and the last one to fly the Orient Line flag. P&O and Orient Line were formally merged in 1960 to form P&O-Orient Lines. In 1964 the Orient Line colour scheme of corn-cream coloured hulls was dropped in favour of P&O's white livery, and Orcades and Oronsay tranferred to the P&O fleet. The name Orient Line was dropped altogether in 1966 when Orsova and Oriana were also transferred to the P&O fleet. Symbolically the last, largest and fastest ship of the Orient Line, the Oriana, wore the Orient Line flag for her final voyage prior to retirement in March 1986. The Oriana managed to survive another nineteen years after retiring and being sold, a career as a floating tourist attraction ending in 2005 with her being scrapped. The memory of this ship and the Orient Line lives on with a P&O cruise ship named Oriana in 1995.