The Cambridge Union has a long and extensive tradition of hosting prominent figures from all areas of public life in its chamber, both state- and international-based, including the Dalai Lama, US presidents Theodore Roosevelt and Ronald Reagan, Bill Gates, Stephen Hawking, UK Prime Ministers Winston Churchill, Margaret Thatcher, and John Major, presidential candidate Bernie Sanders, as well as comedian Stephen Fry.

However, in the political climate of the Hundred Days which ended the Napoleonic Wars, controversial debate topics generated suspicion among university officials who sought to suppress potentially radical thought among students.

On 24th March 1817, university proctors burst into a meeting of the society and the Cambridge Union was temporarily shut down, forbidding future debates from taking place.

By 1821, the Union was permitted to resume debates under strict conditions, including that no political topics relevant to the last twenty years were to be discussed.

[6] Cambridge escaped virtually undamaged from the widespread aerial bombardment during World War II, ostensibly due to a quid pro quo arrangement with Heidelberg, another historic university city.

It is rumoured that during this time the Union became one of a handful of buildings in Cambridge used to plan Operation Overlord and make preparations for the D-Day landings.

[7] Facing financial trouble and extensive rebuilding work, the Union launched a restoration appeal to its life members in October 1945, successfully raising over £3,000 by the end of the academic year.

Several members of the group, including Norman Fowler, Michael Howard and Kenneth Clarke had attended Grammar schools, reflecting gradual changes in university admission at large.

The issue continued to arise in the following decades, with Leonard Miall of St John's proposing a motion in 1935 that certain 'ladies of distinction' be permitted to speak in one debate per term, to no avail.

The daughter of a Labour minister and ex-President of the Oxford Union, Mallalieu's term in office generated significant national publicity and saw a record number of new members joining.

The Union is legally a self-funded charity that owns and has full control over its private property and buildings in the Cambridge city centre.

[13] In January 2015 the Union announced a £9.5m refurbishment project to begin in late 2016 to address major structural problems and to expand existing facilities, subject to approval by planners, to include a new Wine Bar on the ground floor and a Jazz & Comedy Club in the basement (in the old home of the Cambridge Footlights).

[14] Planning permission was received in 2016, and a fundraising campaign to cover the remaining cost was to be launched on 11 March 2017 with a special debate between Jon Snow and Nick Robinson.

[18] The Union launched online membership in late 2015, which allowed any student around the world access to live streams of events for an annual subscription.

One of the Union's most famous debates in recent years was between Richard Dawkins and Rowan Williams in February 2013, on the motion, 'This House Believes Religion has no place in the 21st Century', which was rejected by the assembled members.

The debate, which was televised by the BBC, featured writer and civil rights activist James Baldwin and leading American conservative intellectual William F. Buckley.

At the time the debate received extensive coverage on both sides of the Atlantic, and in subsequent years has come to be seen as a significant moment in the US Civil Rights Movement.

Whilst the Trustees are not intimately involved with the day-to-day running of the Union, they maintain ultimate legal responsibility for the organisation, its assets and status as a registered charity.

On 9 May 2011, the Union launched its online public video service CUS-Connect, whereby recordings of past events and interviews were uploaded for free viewing.

[44] Before 2014, the Union only occasionally live-streamed popular events, with the first ever live stream held on 12 May 2011, in which Stephen Fry debated Radio 1 DJ Kissy Sell Out on the motion: "This House believes that classical music is irrelevant to today's youth".

As part of its bicentennial celebrations in 2015, the Union launched a permanent live streaming service, to be integrated with a new automatic multi-camera rig in the Main Chamber.

[50][51][52][53] In February 2022, the Union hosted the Israel ambassador Tzipi Hotovely in a high-security, balloted event, resulting in protests and minor vandalism of the premises.

[60] Strong opposition to the bill from Liberal Democrats and senior Conservative peers eventually resulted in the shelving of provisions regarding Universities' until after the 2015 General Election.

The union called a referendum on the hosting of Julian Assange on 22 October 2015, arguing that his residency in the Ecuadorian Embassy meant he was outside the jurisdiction of UK law, and thus required the consultation of its members considering a lack of past precedent.