Civil Service Union
In short
The Civil Service Union (CSU) was a British trade union that represented lower-paid staff within the UK Civil Service from 1917 until 1988.
In plain words
It was a group that looked after the rights and pay of workers like cleaners and messengers. It focused on those at the bottom of the government pay scale. The union eventually ceased to exist in the late 1980s.
A simple example
A messenger working in a government office would join the CSU to negotiate for better wages and working conditions.
Why it matters
It provided a voice for essential but often overlooked workers in the public sector. Its history shows how government staff organised to protect their interests during the 20th century.
Easy to mix up
Do not confuse it with modern unions like the PCS, which represent a much wider range of civil servants.