"The cakewalk was originally a plantation dance, just a happy movement [the slaves] did to the banjo music because they couldn’t stand still. It was generally on Sundays, when there was little work, that the slaves both young and old would dress up in hand-me-down finery to do a high-kicking, prancing walk-around.
They did a take-off on the manners of the white folks in the “big house”, but their masters, who gathered around to watch the fun, missed the point. It’s supposed to be that the custom of a prize started with the master giving a cake to the couple that did the proudest movement.”
The Cakewalk was meant “to satirize the competing culture of supposedly ‘superior’ whites. Slaveholders were able to dismiss its threat in their own minds by considering it as a simple performance which existed for their own pleasure”
There is perhaps a pleasant irony in the fact that the slave owners would imitate the slaves’ Cakewalk not realising that it was already an imitation of their own absurd dances and were, thereby, mocking themselves!
EDIT: According to duh doy dorothy, who knows far more on the subject than I do, “slave owners knew cakewalks were simulating formal white dances, they just didn’t allow themselves to believe slaves had the ability to satirize consciously. White people didn’t cake walk until post-emancipation.”
[Sources: Wikipedia | Image One | Image Two | Image Four | Video]