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.

East Indiaman was a general name for any sailing ship operating under charter or licence to any of the East India trading companies of the major European trading powers of the 17th through the 19th centuries. The term is used to refer to vessels belonging to the Austrian, Danish, Dutch, English, French, Portuguese or Swedish companies.