In the first half of the 20th century, London grew rather a lot. Its official government, however, grew not at all.

The result was that, by the 1950s, the city's built up area had achieved a fairly similar form to the one it has today – but the County of London was trapped behind broadly the same boundaries it had held since 1889, and vast swathes of the inner suburbs (Stratford, Acton, Willesden, Tottenham) were left outside.

How modern London was broken up before 1965. The pink area in the middle was the 28 metropolitan boroughs included in London County Council. Image: Wikimedia Commons.

So, in 1957, the Macmillan government appointed a Commission to review how London was governed, under the chairmanship of Sir Edwin Herbert. Its purview covered an area vastly bigger than the then County of London, covering the whole of Middlesex, huge swathes of Surrey, Essex and Kent, and the southern end of Hertfordshire – in effect, the capital's entire urban area.

I've not been able to find a decent map of the Commission’s review area, but the list of councils it covered suggests it looked a lot like the area now enclosed within the M25. Here's an incredibly rough map, just to give you some idea of what we're talking about here:

A very rough map.

In the event, the Herbert Commission didn't include all those places in its proposed Greater London. It dropped Waltham Holy Cross in Essex; Dartford in Kent; and almost all the Hertfordshire authorities, leaving only Cheshunt in.

Another very rough map.

When the Commission published its final report, in October 1960, it proposed the creation of a new Greater London council, which would cover the entire London region and would deal with strategic functions like planning and emergency services. It also proposed a second tier of new London boroughs.

To be precise, 52 London boroughs.

This is of course rather more boroughs than we actually got. Partly that's because the government decided fewer, larger boroughs was the order of the day.

But partly, too, it’s because several of the outer boroughs were eventually excluded from the new authority – mostly because of frantic lobbying from plush commuter suburbs like Esher and Epsom, that remained determined not to be swallowed by the capital. If you've ever wondered why there's a peninsula sticking out of south western London, surrounded by places that are still in Surrey, this is why.

The Kingston peninsula.

At any rate, when the new Greater London finally saw the light of day in 1965, it included not 52, but 33 local authorities (32 boroughs and the city of London). In many cases, these were arranged rather differently to those that Herbert had proposed.

Here, though, is a quick guide to the London boroughs we could have won.

Click to expand.

Some notes on names and boundaries

On the map above, I’ve generally used historic boundaries, rather than speculating about how the authorities might have fiddled with them before launching the new boroughs.

I've used the names of existing pre-1965 boroughs, or post-1965 London boroughs, wherever possible. Where it's not, I've given the boroughs the name of the area that is either the dominant commercial district, or geographical centre, of the borough.

It's worth noting that these boroughs, if they had come into existence, would probably not have had these names, or these exact borders. But since I'm already into the realm of municipal science fiction here, it didn't seem worth worrying too much about it.

Anyway, what you really want to know is where these boroughs are, or what they contain. So here's a lengthy guide, which only a mad person would read in its entirety.

That which survives

Nine of the boroughs proposed survived the numerous iterations of the plan and still exist in the present day. Those ones are easy, so let's do them first.

City of London

Tower Hamlets – Previously the metropolitan boroughs of Stepney, Bethnal Green and Bow.

Kensington & Chelsea – Previously the metropolitan boroughs of those names.

Hammersmith & Fulham – Previously the metropolitan boroughs of those names.

Kingston-upon-Thames – Previously the Surrey boroughs of Kingston upon Thames, Malden & Coombe and Surbiton.

Merton – Previously the Surrey boroughs of Wimbledon and Mitcham, and the urban district of Merton & Morden.

Sutton – Previously the Surrey boroughs of Beddington and Sutton & Cheam, and the urban district of Carshalton.

Barking & Dagenham – Previously the Essex boroughs of those names.

Harrow – The great survivor of London government, Harrow has existed in pretty much the same boundaries since 1934. So, there you go.

Incidentally, today's boroughs of Hammersmith & Fulham and Barking & Dagenham were initially known simply as Hammersmith and Barking. They were renamed in 1979 and 1980 respectively. So, now you know.

Inside the beltway

The vast majority of the Herbert Commission's proposed boroughs covered areas that are inside Greater London today but ended up arranged differently.

There are 37 of these in all (honestly, don’t read all this, it’s not worth it) – but just for information purposes, here's a brief guide to what they would have contained and which boroughs you'll find them in now.

Westminster – The old metropolitan borough of Westminster. Today, that's the whole of the modern City of Westminster south of Oxford Street.

Marylebone – The old metropolitan boroughs of Paddington and St Marylebone. Today, that's the whole of the modern City of Westminster north of Oxford Street.

Clerkenwell – The old metropolitan boroughs of Holborn, Finsbury and Shoreditch. This area – which includes everything from the British Museum to Old Street roundabout – is today broken up between the boroughs of Camden, Islington and Hackney. (It’s also a very odd shape, which makes me wonder if it would have looked exactly like it does on my map, but hey.)

Camden – The old metropolitan boroughs of Hampstead and St Pancras, which is most of modern Camden.

Islington – The old metropolitan borough of Islington, which is most of, well, you can probably guess.

Hackney – The old metropolitan boroughs of Hackney and Stoke Newington, which is most of modern Hackney.

Southwark – The old metropolitan boroughs of Southwark and Bermondsey; basically, the northern third of modern Southwark.

Greenwich – The old metropolitan boroughs of Deptford and Greenwich, which today make up northern Lewisham and western Greenwich.

Lewisham – The old metropolitan borough of Lewisham, in splendid isolation, and without a riverfront.

Woolwich – The old metropolitan borough, today part of Greenwich

Camberwell – The old metropolitan borough of Camberwell, which is the southern bit of modern Southwark.

Lambeth – The old metropolitan borough of Lambeth, which is the eastern half of modern, well, Lambeth.

Battersea – The old metropolitan borough of Battersea, and part of its neighbour Wandsworth. Today this is western Lambeth and eastern Wandsworth. (We’re guessing a bit about which bits of Wandsworth this borough would contain, but we’re happy with our guess.)

Wandsworth – The rest of the old metropolitan borough of Wandsworth.

Richmond – The boroughs of Richmond and Barnes, previously in Surrey, today forming most of Richmond.

Chiswick – The boroughs of Acton, and Brentford & Chiswick. Previously in Middlesex, these are today part of between Ealing and Hounslow respectively.

Willesden – The old Middlesex borough of Willesden, today forming half of Brent.

Hendon – The old Middlesex borough of Hendon, today forming the western half of Barnet.

Barnet – The urban districts of Barnet, East Barnet (both in Hertfordshire) and Friern Barnet, and the borough of Finchley (both in Middlesex). Today this is all in Barnet.

Wood Green – The Middlesex boroughs of Southgate, Hornsey and Wood Green; today the former is in Enfield, the latter pair in Haringey.

Tottenham – The Middlesex boroughs of Tottenham and Edmonton, today in Haringey and Enfield respectively.

Waltham Forest – The Essex boroughs of Walthamstow and Chingford. Today this is most of Waltham Forest.

West Ham – The county borough of that name, repurposed as a London borough. Today that's in Newham. (A county borough, incidentally, was a borough that had all the powers of a county – a sort of primordial unitary authority, basically.)

East Ham – The county borough of East Ham, now a London borough. Today that's in Newham, too. (In the name of simplicity we've assumed the bits of Barking west of the River Roding and – more confusingly – Woolwich north of the River Thames that ended up in Newham would have ended up in the London Borough of East Ham, too.)

Ilford – The Essex borough that today makes up eastern Redbridge. (The north eastern patch, around Hainault, was actually previously in Chigwell, but also ended up in the new Redbridge; we've assumed it would have been in this parallel reality, too.)

Romford – Then an Essex borough, today the northern part of Havering.

Hornchurch – Then an Essex urban district, which today makes up the rest of Havering.

Bexley – The Kent Boroughs of Erith and Bexley, and urban district of Crayford. Today that's most of Bexley.

Orpington – The Kent urban districts of Orpington, and Chislehurst & Sidcup. These are now eastern Bromley and southern Bexley respectively.

Bromley – The Kent boroughs of Bromley and Beckenham, and urban district of Penge, now all safely ensconced in modern Bromley.

Croydon – The old county borough, now the northern half of the London borough of the same name.

Twickenham – Then a Middlesex borough, now part of Richmond.

Hounslow – The Middlesex borough of Heston & Isleworth, now part of Hounslow.

Southall – The Middlesex borough of Southall, and urban district of Hayes & Harlington. These are now split between Ealing and Uxbridge.

Uxbridge – The borough of Uxbridge and urban districts of Ruislip Northwood and Yiewsley & West Drayton. Then they were all in Middlesex, today that's most of Hillingdon.

Ealing – The Middlesex borough of the same name, now part of Ealing.

Wembley – The Middlesex borough of the same name, now the northern half of Brent.

London over the border

And then, there are the six Herbert boroughs which extend beyond today's London.

In the north there's...

Enfield – Which contains the old Middlesex borough of Enfield, as well as the Cheshunt urban district. In the event, the latter was excluded from London, and remained in Hertfordshire.

Woodford – Odd one, this, combining two boroughs which made it into London (Leyton, and Wanstead & Woodford) with an urban district (Chigwell) which remained in Essex. The main thing that these areas have in common now is proximity to the more urban chunks of Epping Forest and the Epping branch of the Central Line. They don't obviously look like a single borough, but let’s assume Herbert and co knew what they were doing.

Moving to the south west...

Staines – The urban district of Feltham (then in Middlesex, now in Hounslow), combined with the urban districts of Staines and Sunbury-on-Thames (today in the Surrey borough of Spelthorne).

Coulsdon – A merger of two Surrey urban districts: Coulsdon & Purley, and Caterham & Warlingham. In the event, the former got swallowed by Croydon, while the latter remains in Surrey as part of Tandridge.

And finally, there were two proposed boroughs that today remain outside London entirely:

Elmbridge – Today a Surrey borough, created from the merger of the urban districts of Esher and Walton & Weybridge.

Epsom – Two Surrey urban districts, Epsom & Ewell and Banstead. Today, the latter is part of Reigate & Banstead, while the former stands alone.

In some ways this bigger London would have made a lot of sense. Most of the suburbs it included which didn't make the final cut – Chigwell, Cheshunt, a huge chunk of Surrey – are contiguous with the capital proper, and serve mainly as dormitory suburbs for it.

Had it come to pass, though, it would still have meant slightly arbitrary borders in some areas. (Such borders are, seemingly, inevitable.) The Kent town of Dartford, for example, merges into the Bexley suburbs, but was ultimately excluded by Herbert. The Hertfordshire town of Watford is served by both London Underground and London Overground trains – yet that didn't make the cut either.

And a larger number of smaller boroughs would probably have meant weaker boroughs too. What this would have meant for the development of London’s government and its infrastructure is unknowable – but today’s city would almost certainly look different in ways we can’t even imagine.

Anyway. We got to talk about borders for a bit and play with a nice map, and isn't that the important thing, really?

Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.

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