One hundred and fifty years is only a tiny time frame in the history of mankind and yet it is only within the last 150 years that the ownership of human beings has been outlawed. And rather than repugnance over the moral outrage of slavery being the cause of its abolition, it took an American Civil War and the deaths of nearly 600,000 people to end it. In the civilized English speaking world (with the exception of the United States) slavery was outlawed before stamps were issued. One of the most interesting stamps issued on this subject is the Jamaica Abolition of Slavery issue of 1921.
Slavery, like the Holocaust, still has its deniers. They typically work to ensure that slavery is never mentioned and that dates concerning its abolition are never commemorated so as to play down the evils of that institution. A perfect example is that in 1962-1963 the United States was issuing commemorative stamps to people like Winslow Homer and never commemorated the centenary the Emancipation Proclamation which freed over 3 million slaves.
In fact, the plight of slavery has received very little attention on United States stamps. Perhaps the most extreme example of slavery denying was the pressure put on the Jamaican government not to issue the Abolition of Slavery stamp it had printed in 1921. The stamp was withdrawn before it was sent to the post offices. Only eight mint copies have survived and four are in the Royal collection.
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