A hoard of Viking coins, silver and jewellery could shine new light on the history of how the Kingdom of England came to exist, after it was discovered by a British amateur metal detectorist. The 186 coins, seven pieces of jewellery and 15 silver ingots were buried around the end of the 870s AD as Anglo-Saxon kings, in what is today England, began to fight back against Viking expansion across Britain.

Detectorist James Mather found the hoard, described as "nationally significant" by archaeologists, in October in Watlington, Oxfordshire and his discovery was announced on 10 December at the British Museum in London. Mather described the range of emotions he felt when he discovered the hoard.

"It was kind of shock, disbelief, excitement, joy, and it all gets a bit kind of surreal because I think you get an adrenaline rush when you find something like this and I wasn't sure, then the questions started. Was I dreaming, am I going to wake up in a minute, what else might be down the hole, who are these coins, who made them, why are they there? And then I thought also, what do I need to do now? And basically the answer was, call the archaeologist," he said.

Vikings had been attacking Anglo-Saxon positions in today's Britain since the late 8th century but at the end of the 9th century, King Alfred of Wessex, Alfred the Great, defeated Viking forces at the battle of Edington, in southwest England. It was a turning point that eventually caused Anglo-Saxon power to be unified as the Kingdom of England in the 10th century.

The find includes rare coins from Alfred's Wessex and from King Ceolwulf II's Kingdom of Mercia. It also contains Viking arm-rings and silver ingots. Gareth Williams, curator of Early Medieval Coinage at the British Museum, said that the mixture of coins was "exciting".

"Now, what's exciting about this hoard, is it's not just Alfred's coins, it has the coins of the last king of Mercia, Ceolwulf the second, and he's a much less well-known king, he's portrayed rather unsympathetically in the surviving historical records," he said.

The hoard will now be assessed by an inquest at which a coroner will decide whether it can be officially regarded as treasure. If it is, Oxford's Ashmolean Museum has expressed interest in helping put it on display.

The find is one of many made by members of the public every year. These finds are recorded by Britain's Portable Antiquities Scheme which can be viewed online. Over 100,000 archaeological finds were reported to the scheme in 2014 and 1,008 finds were declared as treasure. A large percentage of this treasure was found by people with metal detectors, at 90%

"Metal detecting is a great hobby, it gets you out, there is a social side, there's a solitary side, it's healthy, doesn't cost too much money once you bought your machine, and there's always that chance that you might do something good for national heritage, and you might make all your dreams come true if you're lucky," Mathers said.