Mule is style of shoe that has no back or constraint around the foot’heel. mules have history going as back as ancient rome, even though they were not popularly worn until sixteenth century europe. [citation needed] there, mules were bedroom slippers and not worn out in public.throughout the centuries mules have changed in style and purpose.The atlantic slave trade or transatlantic slave trade involved the transportation by slave traders of enslaved african people, mainly to the americas.the slave trade regularly used the triangular trade route and its middle page, and existed from the th to the th centuries.the vast majority of those who were enslaved and transported in the transatlantic