Bunga bunga is a phrase of uncertain origin and various meanings that dates from 1910, and a name for an area of Australia dating from 1852. By 2010 the phrase had gained popularity in Italy and the international press to refer to former Italian Prime Minister Silvio Berlusconi's sex parties, which caused a major political scandal in Italy.
An 1852 issue of Hogg's Instructor states that "bunga bunga" is the name given by locals to a location near Moreton Bay on the eastern coast of Australia.
In 1910 Horace de Vere Cole, Virginia Woolf, her brother Adrian Stephen and a small group of friends, pretended to be the Prince of Abyssinia and his entourage. They obtained permission to visit one of the world's most powerful warships HMS Dreadnought in Weymouth, Dorset, in what became known as the Dreadnought hoax. It was reported that each time the Commander showed them a marvel of the ship, they murmured the phrase bunga, bunga! which then became a popular catchphrase of the time. Adrian Stephen, had this to say about the phrase:
...one of the newspapers published an interview. I think it was supposed to be with one of the assistants at Clarksons, who professed to know a great deal more than he did, and in particular stated that we used the expression "Bunga-Bunga". Anyhow the words "Bunga-Bunga" became public catchwords for a time, and were introduced as tag in music-hall songs and so forth. Apparently the Admiral was unable to go ashore without having them shouted after him in the streets, and I suppose the other officers were treated in the same way.
A 1950 Bugs Bunny short "Bushy Hare" used the phrase "Unga Bunga Bunga" in a nonsensical exchange between Bugs Bunny and a character who represented an Australian Aborigine and who was referred to as "Nature Boy".
In Malay-speaking countries bunga means flower. As such bunga bunga (written as bunga-bunga) is simply the plural form of flower. Possibly, Makassan contact with Australia can explain the existence of the word within the Australian Aborigines culture.