A more probable alternative origin for "cushie" may be "kushti". It was well-established British Army slang by WW1 (British Army slang borrowed a huge number of words from the various Indian languages), and if English Romanies also used it then there's the link that way too. Or there's a Scots word I found here which is a traditional call to cows. Or maybe even "cushion".

There weren't that many black slaves (or ex-slaves) got back to Britain. The Triangular Trade offloaded them in the plantations and shipped sugar and spices back. And with slaves being taken exclusively from West Africa, I can't honestly see how a North-East African kingdom that ceased to exist in 350AD would have been remembered widely amongst West Africans after shipment to the plantations and then brought back by enough slaves/ex-slaves to Britain as to have entered the English language in common usage. It's fun to think that it could have happened though. :-)

Only so many syllables to go round, I guess. I'm assuming that Ham wasn't named after his favourite food, or vice versa. Never mind Germans wishing each other "gute Fahrt" which gets English kids amused, or the English saying "Missed!" in some game or English weather forecasters predicting mist, which gets German kids amused ("Mist" in German roughly equates to "Poo" in English). Or shitzu dogs. Mind you, I might be prepared to believe it for the dogs...

Graham.