Nairobi, Oct. 27 -- When Abraham Lincoln was elected US president in1860, he intended to terminate the spread of slavery into new American territories. Southern states that had held onto slavery began to secede, led by South Carolina, on December 20, 1860, and in 1861, the slave states rebelliously formed the Confederate States of America. In April, the Confederate Army attacked Fort Sumter in South Carolina, instigating a civil war.

A valiant black woman called Harriet Tubman was convinced that the war had to be customised to end slavery. She harnessed her knowledge of routes through swamps, rivers, and wetlands to illuminate a way for Union troops in Maryland.

She had memorised complicated networks of routes during her stint in the Un...