William James Pirrie, 1st Viscount Pirrie, KP, PC, PC (Ire) was a leading British shipbuilder and businessman. He was chairman of Harland & Wolff, shipbuilders, between 1895 and 1924, and also served as Lord Mayor of Belfast between 1896 and 1898. He was ennobled as Baron Pirrie in 1906, appointed a Knight of the Order of St Patrick in 1908 and made Viscount Pirrie in 1921. In the months leading up to the 1912 Sinking of the Titanic, Lord Pirrie was questioned about the number of life boats aboard the Olympic-class ocean liners. He responded that the great ships were unsinkable and the rafts were to save others. This would haunt him forever. In Belfast he was, on other grounds, already a controversial figure: a Protestant employer associated as a leading Liberal with a policy of Home Rule for Ireland.

Harland & Wolff is a British shipbuilding and fabrication company headquartered in London with sites in Belfast, Arnish, Appledore and Methil. It specialises in ship repair, shipbuilding and offshore construction. Harland & Wolff is famous for having built the majority of the ocean liners for the White Star Line, including Olympic-class trio – RMS Olympic, RMS Titanic and HMHS Britannic. Outside of White Star Line, other ships that have been built include the Royal Navy's HMS Belfast; Royal Mail Line's Andes; Shaw, Savill & Albion's Southern Cross; Union-Castle's RMS Pendennis Castle; P&O's Canberra; and Hamburg-America's SS Amerika of 1905. Harland and Wolff's official history, Shipbuilders to the World, was published in 1986.