The Union Steam Ship Company began in Dunedin, NZ in 1875. In 1876 the Union Company took over the Wellington-based 'New Zealand Steam Shipping Company'. In 1877 their vessel Rotorua made the first inter-colonial (New Zealand - Australia) voyage, and in 1878 Union took over the principal trans-Tasman shipping line, McKeckan, Blackwood & Company of Melbourne. In 1890 the company took over the Tasmanian Steam Navigation Company, the main travel operator between Tasmania and the Australian mainland. By 1900 it had gone on to acquire most competitor shipping companies. The Union Company operated with a very large fleet of small to middle sized vessels. The Union was a significant line by world standards, and was bigger than the five largest Australian lines. In 1917 the Union Company was sold to British shipping Company P&O, with operational management remaining out of Wellington, NZ. During the first half of the 20th century the Union Company played a pivotal role in the movement of goods to and from Australasia. It was also one of the largest employers in New Zealand. The Company operated shipping between Melbourne - Hobart and New Zealand between 1891-1959.;;The Company operated offices in Hobart (2 Elizabeth Street), Launceston (184 Cimitiere Street), Devonport, Strahan and Burnie. ;;It stayed with P&O until 1971 when it was sold to a new consortium of Australasian investors, the Australian half being owned by Thomas Nationwide Transport (TNT). The new owners prefixed their ships with the name Union and introduced a stylised red 'U' logo. The 1990s saw the Company moved between a range of major shareholders. By 2000 the last of what was the Union Ship Company was wound up.