( CNN ) -- Can a handful of ancient copper coins from a once-opulent but now abandoned corner of East Africa change what we know about Australian history ? A team of researchers is on a mission to find out . With its glittering wealth , busy harbor and coral stone buildings , the island of Kilwa rose to become the premier commercial post of coastal East Africa around the 1300s , controlling much of the Indian Ocean trade with the continent 's hinterland . Situated in present-day southern Tanzania , during its heyday Kilwa hosted traders from as far away as China , who would exchange gold , ivory and iron from southern Africa 's interior for Arabian pottery and Indian textiles as well as perfumes , porcelains and spices from the Far East . But the Kilwa sultanate 's heyday came to a crashing end in the early 1500s with the arrival of the Portuguese who sacked the city in their bid to dominate the trade routes between eastern Africa and India . From then on , Kilwa never managed to recover its greatness . With its trading network gradually eclipsing , the once flourishing city started to decline in importance . It was eventually deserted in the 19th century , its crumbling , UNESCO-protected ruins offering today a glimpse of its glorious past . But interest in this nearly forgotten East African city has resurfaced lately thanks to the mystery surrounding a remarkable discovery thousands of miles away , in a long-abandoned , remote chain of small islands near Australia 's Northern Territory . Astonishing discovery . Back in 1944 , an Australian soldier named Maurie Isenberg was assigned to one of the uninhabited but strategically positioned Wessel Islands to man a radar station . One day , whilst fishing on the beach during his spare time , he discovered nine coins buried in the sand . Isenberg stored them in a tin until 1979 , when he wondered if they might be worth something and sent them to be identified . Four of the coins were found to belong to the Dutch East India Company , with one of them being from the late 17th century . But the rest of them were identified as originating from Kilwa , believed to date back to the 1100s . The sultanate started minting its own currency in the 11th century . Read this : The dark history of Bunce Island . `` It 's a very fascinating discovery , '' says Ian McIntosh , an Indiana University-Purdue University Indianapolis anthropologist . `` Kilwa coins have only ever been found outside of the Kilwa region on two occasions , '' he explains . `` A single coin was found in the ruins of great Zimbabwe and one coin was found in the Arabian Peninsula , in what is now Oman , but nowhere else . And yet , here is this handful of them in northern Australia , this is the astonishing thing . '' Re-write history ? According to history textbooks , Aboriginal explorers arrived in Australia from Asia at least 60,000 years ago . The first European widely known to have set foot on the continent was Dutch navigator Willem Janszoon in 1606 , more than 160 years before captain James Cook arrived at Australia 's south-eastern coast to claim the territory for the British empire . So how did the five coins from distant Kilwa wind up in the isolated Wessel Islands ? Was a shipwreck involved ? Could it be that the Portuguese , who had looted Kilwa in 1505 , reached the Australian shores with coins from East Africa in their possession ? Or was it that Kilwan sailors , renowned as expert navigators all across the sea route between China and Africa , were hired by traders from the Far East to navigate their dhows ? These are the kind of questions that McIntosh now hopes to answer as he bids to unravel the mystery of how the coins , which are currently stored in Sydney 's Powerhouse Museum , were found in this part of the world . `` We have five separate hypotheses we 're looking to test about how these coins got there , each one quite different from the other , '' says McIntosh . On July 15 , he will lead an eight-member team of archaeologists , historians and scientists to the area where Isenberg discovered the coins . Read this : African roots of the human family tree . `` This is an initial survey ; if we find something then we 'll prepare for a more detailed and focused exploration in specific areas , '' says the Australian professor . `` We are interested in a more accurate portrayal of Australian history that is currently allowed in textbooks . '' The team will embark on its quest for answers equipped with a nearly 70-year-old map on which Isenberg had marked with an X the spot where he found the coins . McIntosh , who was sent the map before Isenberg 's death in 1991 , says he first tried to mount an expedition to the Wessel Islands in the early 1990s but at the time he 'd failed to gather funding . `` In 1992 there was a very limited interest for such a venture , '' he says . `` But we maintained an interest in the Kilwa connection because it was such a famous place in its day -- from the 1100s to the 1300s it was the most prominent port in the entire east African coast , bigger than Mombasa , Zanzibar and Mogadishu . '' `` If you bought these coins in a shop in Kilwa , you could probably get them for a few dollars , '' says McIntosh . `` But in northern Australia , these are priceless in terms of their historical value . ''
African artifacts dating back to 1100s found in remote areas of Australia . They were found in powerful African city state of Lagos , in modern - day Nigeria . Australian professor leading an expedition to discover how they got there .