Nelly was born in Newcastle in 1862, daughter of a Danish businessman Herman Erichsen and his wife. Later they moved to London where Herman became wealthy from the undersea cable boom. Although she could have a had a life of leisure, Nelly yearned to be a painter. She was one of the first women admitted to the Royal Academy School, won several medals and prizes and successfully exhibited her work at Summer Exhibitions and at London galleries. She supported herself working as a book illustrator, which took her to Tuscany, Italy where she tragically died of influenza while working as a volunteer in a refugee camp at the end of World War One.