Nemesis was the first British ocean-going iron warship. She was the largest of a class of six similar vessels ordered by the 'Secret Committee' of the East India Company. Nemesis, together with her sister ships Phlegethon, Pluto, Proserpine, Ariadne, and Medusa, was built by John Laird's yard at Birkenhead and William Fairbairn & Sons at Millwall.

John Laird was a British shipbuilder and key figure in the development of the town of Birkenhead. He was the elder brother of Macgregor Laird. He was one of the first to use iron in the construction of ships.