ONCE upon a time, fields in Derby were awash with blood in some of the deadliest battles the Roman Empire ever fought.

Soldiers marched through the city, encircling vicious barbarians before charging and decimating their enemies.

rom both sides, arrows thwipped through the sky, raining down on all in their path. Entire legions of men were cut down in the chaotic melees.

And all of it in Derby city centre. At the Assembly Rooms, to be precise.

Of course, they were not real armies but delicate, detailed and lovingly crafted miniatures controlled by enthusiasts whose sole aim was victory.

The hobby is called wargaming and for the 27th year in a row it will see players from across the world arrive in the region to pit their armies against those of their fellow gamers.

Derby World Wargames 2012 has been organised by Paul Mills, Richard Waring and Nigel Nicholson, who are collectively known as the Derby Wargames Associates.

Paul said: "Wargaming is a hobby that really captures the imagination of those who take it up. It is very engrossing, very educational and, while it was once very competitive, the emphasis now is on the enjoyment.

"People all over the world play wargames and for years they have all headed to Derby to pit their armies against each other.

"The games have evolved hugely over the years but one thing that has remained is the world wargames and they will be here for a long time yet."

When you think of wargaming, it's easy to think just of the staggeringly popular Warhammer and Warhammer 40,000 series, created and sold by Games Workshop.

That particular strand of the hobby has flourished over the past 25 years, hooking players of all ages from across the globe and giving them a gentle introduction to the world of wargaming.

But that world is far from restricted to just orcs, goblins, elves and Space Marines.

In fact, fantasy is just one battalion in the sprawling army of wargaming.

Nigel, 55, said: "You can look at wargaming in two ways – as a game with toy soldiers or as chess with a thousand pieces."

The most popular strands of the hobby include Ancients (dating from 3,000BC to 1485); Medieval Renaissance era; horse and musket; modern firearms and, finally, more recent warfare from the two World Wars and up to the present day.

Figures mostly range in size from 6mm to 25mm tall.

Those game types – together with the associated models and rules sets – started to come to prominence in the late 1950s and early 1960s and have thrived in popularity since then.

Nigel, of Allestree, said: "Our generation started out with the readily available Airfix plastic figures and kits and that was our gateway to wargaming.

"In my early teens there was a desire to do something more with them than shoot them down with matchsticks and I started looking for ways to make a more rewarding game.

"I visited the local library, found the now classic Grant and Featherstone books on wargaming and that was that."

Richard's introduction to wargaming came when he went to college and discovered a society dedicated to the hobby. And Paul's interest was piqued when he was about 10 years old, when tabletop gaming was featured in a TV series.

It is a hobby in which you can lose yourself, spending hours painstakingly painting the tiny figures.

Paul, 45, said: "The amount of time people spend on the hobby really depends on how much you want to get into it.

"People who can paint take a great amount of pride in their miniatures. But if you can't paint, you can buy them already done and the level of detail is astonishing."

In Paul's house in Stretton there is a "wargaming room" where thousands of lovingly crafted figures line the shelves. One that stands out is a mounted soldier carrying a regimental flag. That detail is impressive enough but then the eye falls on the horse, with its straining muscles shaded to perfection and a leopard skin jacket wrapped around its neck.

So what is it about the hobby that truly grips those who venture into it and keeps them interested for decades?

"There are many reasons why people first get into it," said Richard, 58. "Some people are interested in the painting of models and the level of detail that goes into it, while others are interested in the historical background of particular battles.

"Some get into it through interest in the Second World War. But however the introduction comes, it is the enjoyment of the hobby that keeps people there.

"And if you are interested in the Second World War and re-fight the Normandy beach assaults, for example, then it may be that at some stage you are introduced to the American War of Independence.

"Then wargaming has a fresh new appeal, with new models to paint, new armies to recreate and new battles to refight."

Refighting battles is when two or more gamers reimagine a famous action, such as the Battle of Gettysburg in the American Civil War. The aim is not to faithfully recreate the outcome but to better it.

Paul says: "Put simply, you try to do better than the real-life generals did on the day. If you are playing as the army that won, you want to win with fewer casualties; if you are the army that lost, then really, you just want to win."

Table-top battles work by players deciding where they want to advance their armies across the playing surface.

When the opposing forces get into contact or shooting range, dice are used to create some uncertainty in the result of the fighting.

If it is a skirmish, the forces will eventually come together and the winner is decided with a complex yet easy-to-learn formula combining the strength and armour points of the soldiers and more rolls of the dice.

Victory is earned either by destroying the opposing army, making it to the opposite end of the gaming field or by lasting until the time runs out.

Nigel said that, the more time people spend playing, the more they come to learn about the armies they are commanding.

He said: "Some military regiments can be traced through the years and through the various wars and conflicts and that is very appealing to some wargamers, too.

"People become very interested in the history of the regiments they play with and try to follow them through the ages."

The Derby World Wargames were originally held at the Assembly Rooms before moving to the University of Derby's Kedleston Road campus. This year, they are at the Castle Donington International Exhibition Centre, in October. Around 2,000 people are expected to attend.

Paul said: "We used to get players from all over the world, from the USA to South Africa. It's still as well attended but we tend to get people from Europe now.

"We have a lot of Italian players, French and German wargamers, who make the trip to Derby every year."

It's not just the wargamers themselves who can attend the world games – in fact, there tends to be more spectators than players.

Richard, of Littleover, said: "The game has to evolve and we have to introduce a new generation of players to wargaming. If it doesn't change along with a changing market then it will grow stagnant and die.

"That's why it is important to show people what it is about, the different ways you can play and, at its heart, how fun it is.

"It's a hobby like any other – something you pour your time into and you enjoy. And the more people who play it, the more fun it becomes."

To find out more about wargaming and the Derby World Wargames, visit www.worldwargames.co.uk