Near the end of 1861, President Abraham Lincoln became obsessed with an unusual document. The President called it his “slave map”. Since 1808, importing slaves into the United States was prohibited, but internal slave-trading continued apace, and the slave population would eventually peak at four million. In 1860, of all the approximately 1,5 million free families in the fifteen slave states, roughly 25% held slaves.

When Abraham Lincoln won the 1860 election on a ticket of no new slave states, the South broke away to form the Confederacy. This marked the start of the Civil War.

In the map, Lincoln saw testimony that the American south was not a uniform bloc. Areas of heavy slavery—the darkened banks along the Mississippi River, for example—tended to be secessionist, but the areas in between held the hope of pro-Union sympathy. Unlike traditional cartography, the map was designed to portray political terrain and, in Lincoln’s mind, moral terrain (“Why Abraham Lincoln Loved Infographics”, New Yorker)

The war effectively ended slavery before the Thirteenth Amendment to the United States Constitution (1865) formally outlawed the institution throughout the United States.

It’s amazingly tragic that 150 years after Abraham Lincoln signed the Emancipation Proclamation (1863), the world must still combat the buying and selling of humans. Although slavery is illegal internationally, it persists as a problem today with 29.8 million “modern slaves” worldwide, including children held against their will primarily for labour or sex; more than in 1860, when there were 25 million.

Slavery is the possession and control of a person in such a way as to significantly deprive that person of his or her individual liberty, with the intent of exploiting that person through their use, management, profit, transfer or disposal. Usually this exercise will be achieved through means such as violence or threats of violence, deception and/or coercion.

Slavery pre-dates written records and has existed in many cultures. In pre-industrial societies, slaves were economically extremely important to those who benefited from them. In modern mechanised societies, there is less need for sheer massive manpower. However modern slavery continues with slavery-like practices (such as debt bondage, forced marriage, and sale or exploitation of children), human trafficking and forced labour.

The first edition of the Global Slavery Index (2013) by the Walk Free Foundation provides a ranking of 162 countries around the world. The countries with the highest numbers of enslaved people are India, China, Pakistan, Nigeria, Ethiopia, Russia, Thailand, Democratic Republic of Congo, Myanmar and Bangladesh. Taken together, these countries account for 76% of the total estimate of 29.8 million in modern slavery.

The country with the largest number of people in modern slavery is India, which is estimated to have between 13,300,000 and 14,700,000 people enslaved. The country with the second highest absolute numbers of enslaved is China, with an estimated 2,800,000 to 3,100,000 in modern slavery. And the country with the third highest absolute number is Pakistan, with an estimated 2,000,000 to 2,200,000 people in modern slavery.

Mauritania is the country with the highest estimated proportion of its population enslaved of any country in the world.  The West African country, with its deeply entrenched system of hereditary slavery, is thought to have 150,000 slaves in a population of only 3.8 million. Haiti, where child slavery is also widespread, is in second place, and Pakistan one place below.

And here are some chilling statistics put together by the SumAll Foundation: The lifetime profit on a brick-making slave in Brazil is $8,700, and $2,000 in India. Sexual slavery brings the slave’s owner $18,000 over the slave’s working life in Thailand, and $49,000 in Los Angeles.

The global median cost per slave has not changed much from $134 (inflation adjusted USD) in President Lincoln’s day to $140 today. On average today, a person is a slave for six years, after which the person usually escapes, repays the debts holding them, or dies.

SumAll has learned from speaking with several anti slavery organizations that It’s vital to look at why people are still enslaved in modern times. If we only focus on rescue, we may save some, but traffickers will simply enslave others in their place.

Modern slavery will not be eradicated until business leaders ensure their supply chains are slave-free. Walk Free Foundation is working with the world’s business leaders to help them understand how they can play a role in ending modern slavery. Will they be receptive?

Abraham Lincoln was assassinated in April 1865 as part of a conspiracy to revive the Confederate cause. His endeavour is yet to be completed:

I have always thought that all men should be free; but if any should be slaves it should be first those who desire it for themselves, and secondly those who desire it for others. (Abraham Lincoln, March 17, 1865)