Human Population

In a comment to a previous post, Happy 4th of July, Akshar wrote, “in 1789 George Washington became the first democratic president of such a large nation directly at odds with the largest empire on earth.” What caught my attention were the words “large nation” and “democratic.”

Today when we talk of large nations, we figure hundreds of millions of people. But things were different in the past. By today’s standards, the newly minted United States of America was tiny, Around 1776, the total population of the 13 former colonies was around 2.5 million people. That’s less than the present population of Pune (a moderately big city by Indian standards), which is over 3 million people.

And how big was Great Britain at that time? Estimates of the population range from 7 to 10 million. That means the combined population of England, Scotland and Wales was less than half the present population of Delhi or Mumbai. Those countries had tiny populations.                            ∇

What about democracy? 

Certainly Washington was democratically elected but democracy was not the universal adult franchise that we associate with present-day democracies. In the good old days of Washington and Jefferson, only white males who had property had the privilege of voting. Females could not vote, non-Whites could not vote, and people without property could not vote. Let’s guess that only about one-sixth of the population could vote.

I am guessing that only about 40,000 people of the United States had the vote. Curiously small population. But let’s put that into the context of human population in general.

Human Population

For most of human history, humans were a minority in the world. It is generally understood that modern humans have existed for around 200,000 years, and that humans first migrated out of Africa around 100,000 years ago. For nearly all of 200K years, human population was less than 1 million people. Indeed it is estimated that the human population passed through a bottleneck about 70K years ago when the population was reduced to as little as 10,000 individuals. (See the Toba catastrophe theory.)

These are all estimates, of course, since no one was doing any global census. They are accurate to an order of magnitude, which is all we need to know to get a feel for what it was like in the past.

2K Years Ago

Anyway, around 2000 years ago (the start of the Common Era calendar), the population was 170 million. The population hardly changed over hundreds of years. By the year 700 CE, the population was around 190 million. Imagine, adding 20 million to the total in 700 years. (India alone adds more than 20 million in one year.)

Around the year 1500 CE, the population was around 425 million. The population was heavily concentrated mainly in the Gangetic plain in India, and in Eastern China, and a bit in Western Europe. Around the year 1300 CE, world population crossed half a billion.

World Population 250 Years Ago

World population around the time of the Declaration of Independence of the US (1776) was 850 million. So with 2.5 million people, the United States had less than one-third of one percent of the world’s population. Wow. That’s a tiny, tiny nation. My guess is that India’s population was around 250 million. India was 100 times larger than the US at that time.

Sometime around the year 1800, the world population crossed 1 billion. It took nearly all of 200,000 years to get to 1 billion — and to reach 7 billion, it took only around 200 years! Imagine — 1000 times as fast.

What caused the population explosion? And was Thomas Malthus wrong? And why was Paul Ehrlich so wrong and Julian Simon so right? Why do people freak about about population numbers? Is democracy over-rated? Should we have world government? Is the earth running out of resources? Will climate change doom humanity?

Lots of interesting questions. But for now, watch this video – Human Population Through Time.

Author: Atanu Dey

Economist. View all posts by Atanu Dey