Development of the Re.2001 began shortly after the preceding Re.2000 got rejected by the Regia Aeronautica due to several issues surrounding its engine. Taking over much of the 2000’s design, Reggiane installed a new Alfa Romeo inline engine into the aircraft and created the Re.2001, dubbed Falco II.
Thanks to the new power plant, many of the previous issues were addressed, as the new engine was more powerful and reliable, being a licence-built version of the German DB 601 engine. Despite successfully passing trials, the Re.2001 faced a slight delay in its introduction into service as certain modifications had to be made on request by the Regia Aeronautica. Eventually, the Re.2001 entered service in September 1941 in Italy, and saw its first serious fights in May 1942 over Malta.
The Re.2001 CN was subsequently developed to allow the aircraft to fill the night fighter role. Compared to the base models, the night fighter version of the Re.2001 most notably received exhaust pipe dampers and replaced the original 7.7mm wing-mounted machine guns with 20mm cannons suspended in under-wing gondolas. Additionally, the aircraft received an appropriate black night fighter camouflage.
Most of the Re.2001 CNs assisted in the defence of the Italian mainland in the later stages of WW2. Only a couple dozen aircraft of the night fighter modifications were built, of the total of around 230 Re.2001s produced.