Alternatively described by Richard Rogers as “the culmination of a master architect’s life work” and Prince Charles as “a giant glass stump”, the plans by German modernist Ludwig Mies van der Rohe for an office tower in the City of London proved to be controversial from the start.

The project’s failure to be realised is often blamed on power plays from the peerage, prime minister and prince – although this tale of personal and political intrigue is more accurately the result of a sudden and extreme change in public opinion, and a shift against modernist architecture.

In Thatcher’s London, historical pastiche and an obsession with preservation came to dominate architectural and mainstream culture. Increasingly, modernism was misunderstood as a postwar project to produce brutal, inhuman forms and poor-quality mass housing. Films like A Clockwork Orange only further cemented the popular conception that modernism meant social dystopia, not the benefits of social democracy.



Of course, the landscape of British architecture has been inhospitable to modernism since the concept was invented. While Italian Futurism and Dutch De Stijl were sweeping away the cobwebs of the 19th century, we Brits were poking about with quaint, folksy Arts and Crafts. While the German Bauhaus and French Esprit Nouveau were revolutionising aesthetics and space, Britain was praising the prudent neoclassicism of Edwin Lutyens.

Indeed, as a country, our propensity to damage or demolish modernist gems has been matched only by our determination to deny their designers planning permission in the first place. This was undoubtedly the case for Mies, one of the greatest architects of the 20th century.

Architect Ludwig Mies van der Rohe in his Chicago apartment in 1964. Photograph: Werner Blaser/AP

Originally commissioned in 1963 by Lord Peter Palumbo, the proposal endured more than two decades of spectacular drama – planning reviews, popular outrage and press vilification that culminated in a bitter public inquiry and the scrapping of Mies’ masterpiece.

His scheme for Mansion House Square is infamous more than it is famous – every architect over 40 in Britain has a strong opinion about the work. And yet these views are often held with almost no knowledge of what was actually designed as very little information about the work has existed in the public realm, until now.

The imagined site is at the central junction of the City, surrounded on all sides by great works of architecture. To the north is Lutyens’ neoclassical Midland Bank, currently being converted into an alleged 6-star luxury hotel. To the south-east is Sir Christopher Wren’s St Stephen Walbrook church, whose delicate coffered dome sits above an altar designed by Henry Moore. Across the road is Sir John Soane’s Bank of England and beyond that the Royal Exchange. Directly opposite stands the lord mayor’s official residence, Mansion House – a structure of equal importance to its neighbours, if not equal in beauty. Indeed, the eminent historian Sir John Summerson once described this squat building as “a striking reminder that good taste was not a universal attribute in the 18th century”.

Mies’ proposals: ‘the culmination of a master architect’s life work’ or ‘a giant glass stump’? Photograph: John Donat, courtesy Drawing Matter and Real foundation

The City of London has operated as a pseudo-autonomous entity within Britain since the Norman conquest in 1066. The contradiction of this limited freedom is that for almost a millennium the City has been extremely progressive economically, and yet remained extremely conservative politically.

When 80% of London burnt down in 1666, its mercantile class did not hesitate to bypass the king to get the City rebuilt as quickly as possible. In order to do so they invented real estate capitalism, a development that would pave the way for both the industrial revolution and the mighty empire of Foxtons.

[This is] yet another giant glass stump, better suited to downtown Chicago than the City of London Prince Charles

Mansion House itself is claustrophobically hemmed in on all sides, appropriately overshadowed by the Rothschild tower. This is why one of the most important elements of Mies’ vision was the creation of a large public space to the east of the site. In some respects, this was the greatest genius of the scheme – Mies took a scrambled, dangerous street pattern and made one intervention to rationalise it into a nearly perfect geometric square. He carved out a serene ceremonial court directly in front of one of London’s most important seats of power. The reinstatement of the underlying Roman grid would have undone hundreds of years of urban chaos.

The immense level of detail produced by Mies makes it clear he had every hope the building would be realised as his last work. Years were spent developing specific bronze door handles, mullions tests and an ashtray, as well as the full set of construction drawings specifying the most minute of elements (including a full list of all the tree species for the square and a novel heating system to keep travertine steps dry).

Mies completed work on Mansion House Square just a few weeks before his death in 1969. One of his last acts as an architect was to carefully choose a place for the flagpole in the square. The attention he paid was commensurate to his belief that this new space would reinforce the “heart” of the City, not only expanding the performative possibilities of mayoral events, but also creating a peaceful focus for the financial district.

James Stirling’s No 1 Poultry on the site of Mies’ proposed Mansion House Square. Photograph: Alamy

His instructions indicate the square was to be programmed for music festivals, concerts, exhibitions, and flower markets. Such a civic gesture did not appear problematic when pre-planning was granted in the mid 1960s – precisely because it was such a positive addition to London. However, by the mid 80s public space had become a real source of panic for both the City and the British government.

The 80s were a famously tumultuous decade for the UK, as Thatcher’s reforms radically transformed the basic fabric of society. Strikes and civil unrest in London were common, from dockworker and printers’ union disputes in the east to violent race riots in Brixton and deadly poll-tax protests in Trafalgar Square. Thrown into this mix were anti-Apartheid marches and IRA bomb attacks. Large crowds – whether gathered out of civic pride or disobedience – were no longer desirable in the city. In effect, public space had become dangerous.

Urban policymakers responded by preventing the formation of new public spaces, often by claiming existing structures had “historical merit” and thereby blocking the development. There is certainly something suspicious about the fact that surrounding buildings were only listed in the late 1970s when Mansion House Square looked to be going ahead. Asked to testify at the 1984 public inquest, the Russian emigre architect Berthold Lubetkin said: “It is inconceivable that such a generous and unique gift to the City should be discarded in the name of a vague antiquarian pedantic prejudice.” Sadly, it was quite conceivable.

While the City may or may not have been using historicism as a smokescreen for an anti-public space agenda, one key personality really believed what he said: the Prince of Wales. In spite of his friendship with Lord Palumbo (they were on the same polo team), Charles became determined to quash what he saw as a modernist abomination.

Mies van der Rohe’s Mansion House Square proposals. Photograph: John Donat, courtesy of Drawing Matter and Real foundation

In his “carbuncle” speech at Riba’s 150th anniversary dinner in May 1984 the prince specifically criticised Mansion House Square, saying: “It would be a tragedy if the character and skyline of our capital city were to be further ruined and St Paul’s dwarfed by yet another giant glass stump, better suited to downtown Chicago than the City of London.”

His intervention would not be the prince’s only unorthodox foray into planning processes – he also ridiculed any National Gallery extension that wasn’t Classical; advocated strongly for the modernist buildings around Paternoster Square to be destroyed (which they were); and more recently penned a personal letter to the Qatari owners of the Chelsea Barracks, one royal to another, to prevent Richard Rogers’ project from being built. Lord Palumbo responded: “I can only say God bless the Prince of Wales, and God save us from his architectural judgment.”

In transcripts of the 1984 public inquiry into Mansion House Square it is remarkable how many specious arguments were allowed to slip by unquestioned: first the scheme was considered too radically different from its context; and then it was argued it was not radical enough.

James Stirling captured the mood when he said: “Some consider the design old-fashioned, reflecting ideas current in the 1960s or earlier. In my opinion this is a viewpoint influenced by the journalists, showing an over-concern for both fashion and the style of architecture that is called ‘post modernist’. I think this position is very much of the moment, but of little real value to any events of substance.”

There were also worrying undertones of a renewed nationalism, curiously absent from the 1960s records. At one point a City apparatchik denounced Mies as a communist and a German. Apparently neither of these was a desirable quality in an architect (even if neither claim was strictly true: he was a naturalised American).

After the tower and square were definitively axed, Palumbo turned to the same great architect (a British one this time) that had so valiantly defended Mies’ scheme: James Stirling. The work that was eventually built, called One Poultry, is a pink postmodern confection with striped stonework. Like Mies, Stirling’s work was the subject of much controversy, and several attempts to modify or demolish the building have been averted at the 11th hour.

As is typical of governance and planning in the UK, it is only well after the fact that common sense prevails: One Poultry was recently given Grade II* listing, and the City of London is now considering pedestrianising the entire junction. In the end we may see the same restful quality of public space that Mies imagined as far back as 1963, although without his design for the square it will be immeasurably impoverished.

The final twist is that at just 19 storeys, the bronze-clad, amber-glass tower would have been less than half the height of the Gherkin, and not even a fifth of the Shard. For all the outrage it caused in the 1980s, Mansion House Square wouldn’t even make the top 100 tallest structures in London today. Ironically, if Mies’ scheme had been delayed by another decade, the work would probably have appeared banal in the context of so many other corporate towers.

For the first time in more than 30 years, Mansion House Square is to be presented to the public at an exhibition at Riba and a book being funded on Kickstarter by Real foundation.

Follow Guardian Cities on Twitter and Facebook to join the discussion, and explore our archive here