Before the census of 1801 all estimates of the population of London are open to question. The following table gives the best available estimates in round figures. The census data for the 19th and 20th centuries have been rounded up to the nearest 1,000. It should be noted that, because of the out break of the Second world War, the 1939 figures are an estimate.

The tables give figures for both the City and "Total London". The latter term is here meant to cover both the City and the London Hinterland as understood by Londoners and others in the various historical periods. In the early mediaeval period it would have included the City, Southwark and Westminster, for example. In modern times, it covers what we know as Greater London. Separate figures are often quoted for the area administered by the London County Council (LCC). These exclude the City and some of the outer suburbs and can cause confusion. The LCC was a political entity that operated from 1888 to 1965. It made a very real contribution to the development of London and enjoyed wide-ranging powers, but it did not represent "Total London" in a demographic sense.

To give some kind of perspective, the figures for "Total London" are also expressed as a percentage of the total population of England or, after 1801, of England and Wales. The effect of the Black Death in the mid 14th century is a matter of great dispute and no really accurate figures are available. There may or may not have been a catastrophic fall in the populations of London and England between 1300 and 1400. The figure for 1400 given below is a very rough estimate which takes account of the obvious and accepted fall in numbers between 1300 and 1550.

Perhaps the most surprising aspect of the table is the fact that the City of London, the "Square Mile" was at its most populated at the end of Elozabeth's reign! Perhaps as many as an astonishing 150,000 person were crammed into that small area. The effects of the Great Plague and the Great Fire do seem to be measurable but not greatly significant. It is not until the rise of "Suburbia" at the beginning of the Industrial Revolution that we begin to see significant falls in the resident population of the City. From the first census in 1801, it is a story of steady decline until the Second World war. Following that event, the City's population just about halved and has remained hovering around 4,000 souls ever since. It is a bleak place indeed on a wet winter's weekend when the commuters are gone and the streets are occupied only by the odd stray tourist and the pigeons.

TABLE 1: Estimates From Roman To Georgian Times

Date

City

Total London

% of England

150	30,000	?	?0.5 - 1.0
250	45-50,000	?	?0.5 - 1.0
450	??10,000	?	<0.5
1025	?	10,000-12,000	?1.0
1100	?	20,000+	?1.0
1200	?	50,000	?1.0
1300	?	100,000	?1.0
1400	?	?50,000 - 60,000	??
1550	56-69,000	61-75,000	2.5
1600	131-152,000	200,000	5.0
1650	132,000	400,000	7.5
1700	93,500	575,000	11.5
1750	?	675,000	11.5

TABLE 2: Census Figures For 19th And 20th Centuries

Date

City

Total London

% of England + Wales

1801	129,000	1,097,000	12.3
1811	121,0001	304,000	12.8
1821	125,000	1,573,000	13.1
1831	124,000	1,878,000	13.5
1841	125,000	2,208,000	13.8
1851	129,000	2,652,000	14.8
1861	113,000	3,188,000	15.9
1871	76,000	3,841,000	16.9
1881	51,000	4,713,000	18.1
1891	37,000	5,572,000	19.2
1901	27,000	6,507,000	20.0
1911	19,000	7,160,000	19.8
1921	14,000	7,387,000	19.5
1931	11,000	8,110,000	20.3
1939	9,000	8,615,000	20.8
1951	5,000	8,194,000	18.7
1961	5,000	7,992,000	17.3
1971	4,000	7,452,000	15.3
1981	4,000	6,713,000	13.7
1991	4,000	6,394,000	13.0