The 19th and 20th centuries marked the time of most change in Bushey, especially between 1860 and 1960. The population rose 28-fold within 200 years, from 856 in 1801, to just under 24,000 today. The expansion was for many reasons, one of the main ones being due to the boom in industry caused by the railway in the early 20th century. A result was that many new jobs were created in and around Watford, and in the early 1920s, Bushey's first council houses were built. More housing was later built for the service families working in defence organisations in Stanmore and Northwood. The expansion eventually died down because much of the land in and around Bushey was protected under the Metropolitan Green Belt after the Second World War.