10/08/2026
πOn this day in West Middlesex π
10th August 1939 - Britain practises the blackout
Did you know that Britain was practising blackouts before the Second World War had even begun?
The first blackout exercise had taken place earlier that summer, but on the evening of 9th August 1939 a nationwide blackout was held, continuing until 4.00am on 10th August. Across West Middlesex, homes and businesses were required to extinguish or carefully cover their lights, while Air Raid Precautions (ARP) wardens patrolled the streets to ensure the regulations were being observed.
The exercise reflected growing concerns that Britain could soon face devastating night-time air raids. The Air Ministry had forecast that enemy bombers might launch sudden attacks causing widespread destruction and heavy loss of life. Military planners believed that by plunging towns and cities into darkness, enemy aircraft would struggle to navigate and identify their targets.
Public Information Leaflet No. 2 reminded civilians that everyone had an important role to play, stressing that the blackout would only be effective if every household and business complied with the regulations.
Journalist W. F. LEYSMITH, reporting for The New York Times, described the atmosphere of the exercise:
"Among many observers there is an uneasy feeling that in real war some bombers could sneak through on a night like this and, following the River Thames, which could never be entirely blackened out, strike hard and fast at the heart of the metropolis."
Despite the eerie darkness, everyday life continued. Food was still transported to markets, newspapers were printed and delivered, and trains ran to schedule. To prevent even the smallest glow being seen from the air, locomotive cabs were covered with tarpaulins, passenger carriages were darkened, and traffic lights shone only as tiny coloured pinpoints.
Less than a month later, on 1st September 1939, Germany invaded Poland, and the blackout became a permanent feature of daily life across Britain.