The discovery of the elements, now discredited, was made by Enrico Fermi and a team of scientists at the University of Rome in 1934.
Following the discovery of nuclear fission in 1938, it was realized that "elements" found by Fermi were actually a mixture of barium, krypton, and other elements.
The actual elements were discovered several years later, and assigned the names neptunium and plutonium.
[1] Already in 1934, Ida Noddack had presented alternative explanations for the experimental results of Fermi.
[1] Fascist authorities wanted one of the elements to be named littorio after the Roman lictores who carried the fasces, a symbol appropriated by Fascism.