How South Holland could have looked in the Iron Age

That was back to the era of the Iron Age, which ran for an 800-year period from the first use of iron in around 750 BC until the Roman Conquest, which began in AD 43.

“What surprised me during the research was the extent of Iron Age finds in the district, considering the inhospitable landscape,” Mr Henderson said.

“The sea was encroaching much further inland than it does today, and only ‘islands’ of slightly higher land afforded any opportunity for settlement. Our Celtic ancestors in this area must certainly have been a hardy people.”

In his South Holland Miscellany series, which focuses on the area’s geography, history and personalities, Mr Henderson explains: “The inhabitants had no written language.

“What written knowledge we have of life in Britain at the time comes from ‘foreign’ sources - the Greek and Roman civilisations. What we know of life during the British Iron Age is therefore down almost entirely to archaeological evidence. Several thousand domestic settlements have been traced across Britain, and countless examples of pottery, tools, jewellery and other artefacts.

“The inhabitants of Britain prior to the Roman Conquest are generically described as ‘Celtic’, sharing similar (but not identical) cultural traits with their Celtic counterparts in continental Europe. The Celtic culture is generally agreed to have originated in continental Europe around 1200 BC, expanding into Britain around 750 BC…’

In the Bronze Age, which preceded the Iron Age, the sea waters lapped as far inland as Peterborough, Bourne and Billingborough.

“The edges of the higher land surrounded the low, flat basin of The Wash,” Mr Henderson continues. “In the Iron Age, the sea had retreated north-eastward. It is difficult to pinpoint where the open sea ended and tidal flats began, complicated by the fact that these delineations were not static – they would have changed over time.”

Mr Henderson’s map shows an impression of how the Iron Age coastline of South Holland could have looked.

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“You can see that, in broad terms, the coastline had retreated to the line where later coastal medieval towns and villages would evolve. Three main river estuaries are shown: Bicker Haven, The Welland Estuary and the Nene Estuary. Tidal waters may well have been quite extensive, meeting and mingling with the fresh waters flowing from the higher land surrounding The Wash.”

Bicker Haven would much later in time become a busy trading port, said to be the second busiest after the City of London – full of fishing and trading boats.

“Of particular interest is the discovery of several Iron Age saltern sites in South Holland,” Mr Henderson says. “They are all sited in and around the River Welland.

“Salterns are salt making sites, where salt is extracted by evaporation from sea water. So, sea water was reaching as far inland as Crowland and Deeping St Nicholas. The Iron Age marks the earliest point at which salt production occurred in Britain.

“Whereas salt today is pretty much taken for granted, it’s difficult to overestimate its importance – and value – on earlier times, particularly for food storage and preservation.”

Finds from the Iron Age era are concentrated around the southern and western fringes, Mr Henderson has found. These have been at Crowland, Cowbit, Deeping St Nicholas, Spalding and the western edges of Pinchbeck, Gosberton and Donington.

Among the discoveries include evidence of a late Iron Age settlement and saltmaking site at Clay Lake in Spalding. Finds in 2011 included pottery, animal bone and briquetage (a coarse ceramic material used to make evaporation vessels and supporting pillars when extracting salt from brine or seawater.)

Signs of a possible late Iron Age to early Romano-British saltern were also discovered in the Horseshoe Road and Holland Park area of Spalding in 1999.

Mr Henderson said: “We don’t know for sure what social structures were in place during the early Iron Age, but there is one truism about the human race; we are tribal by nature.”

And he says there is every reason to suspect that there will have been some forms of social and political groupings.

The Iron Age is said to have seen more formalised field systems being introduced, with banks and ditches suggesting property and ownership boundaries.

He explains: “Around The Wash during the approximate time of the Roman conquest seems to have been an undefined, perhaps even overlapping, boundary between the Corieltauvi (to the west) and the Iceni (to the east) tribes.

“Whether the area we now call South Holland was under the control of one or both of these tribes is a matter of conjecture. A small hoard of Corieltauvian coins were found at Whaplode Drove, suggesting the territory extended at least that far east.”