The Black Death paid its first deadly visit to Portsmouth in 1348; we don't have anything in the way of figures for those affected, nor the number of fatalities, as French raiders attacked the town three times in the four decades following the outbreak, and almost anything in the way of records went up in huge clouds of smoke.

However, we can safely assume that a large proportion of the population became infected, as in other towns and cities, and that the number of people who would have died would also have been high - the mortality rate for Black Death was, and still is, whenever it surfaces somewhere in the world, extremely high and people who survive the infection are exceptionally lucky, even with today's medicines.

The Black Death, or Bubonic Plague, has been around for millenia, but until the 1340s, it appears to have been absent from Europe for around a thousand years.

It seems to have suddenly reappeared in Italy, carried to ports by the fleas living in the fur of the ships' rats - rattus rattus - usually referred to as the black rat.

The map below shows how quickly it then

spread across the continent in the space of just a few years. Seaports were especially at early risk, as trading vessel were moving freely between countries at this time.

Leaving aside Portsmouth's lack of written records, the figures for the rest of the country and for Europe as a whole are very hazy in general, probably because so many people were dying very quickly and those who escaped the first wave of infections were fleeing to places as remote as possible, to avoid catching the disease.

Various accounts give the percentage of Europe's population who died in the four year period from 1347 as thirty per cent, fifty per cent and even seventy per cent. For many years, the perceived wisdom was that the British Isles lost about one third of its population, but more recently historians have amended that thinking and are fairly confident that the figure was about fifty per cent.

Black Death was - and is - a particularly nasty disease (not that there are any nice ones) because of the way it affects those who contract it.

The first symptom in a victim was a severe headache, followed by a growing feeling of weakness, until the sufferer became to weak to stand, let alone walk; after about three days, the lymph nodes in the armpits and groin would start to swell, until they became roughly the size of goose eggs.

These swellings were called "buboes", and from this the disease was given its proper name, Bubonic Plague.

The victim's heart would struggle increasingly to pump blood through the affected areas, but blood vessels would rupture, causing widespread haemorrhaging that blackened the skin - hence the name Black Death - and before long the patient would begin coughing up blood.

This would be quickly followed by a collapse of the nervous system, causing limbs to spasm and subjecting the victim to intense pain. Fortunately, death then followed fairly quickly, sparing the victims further prolonged agony.

Unfortunately, long before the first real symptoms appeared, the victim's lungs would already have become infected, and as he or she breathed out, microscopic spores would be released into the atmosphere, which were then breathed in by unsuspecting people in the vicinity, passing on the infection rapidly.

Thus it was that, although victims generally died within a week of first becoming infected, the disease was already moving on from them rapidly, spreading through crowded communities like wildfire - there are accounts of some villages being wiped out entirely.

Efforts were made to quarantine villages where the Black Death appeared - feudal laws actually forbade peasants leaving their village without their lord's permission - but it was impossible to police this and individuals and whole families fled, usually under cover of darkness, often taking the disease with them, albeit unknowingly at the time.

Eventually, as large percentages of the population were carried off by the

disease, the rate of plague spread began to slow down, either because the survivors weren't being packed so closely, but possibly because some people wre actually immune to the disease.

There are accounts of gravediggers handling hundreds of corpses and doctors and clerics attending dying victims, surely exposing themselves to infection - and yet they did not display any symptoms and lived to tell the tale.

Other people believed that the plague was a curse from God and paid for priests to bless and absolve them, or held meetings, where they whipped themselves as a means of atoning for their sins and spent hours crying out for forgiveness.

As the Black Death began to die out at last, those people who had survived began, in some cases, to believe that they were "special", chosen by God to survive, because they were more

pious and deserving than those who had been killed by the disease.

However, although medical knowledge in Europe at the time was pretty basic, some doctors realised that they had to modify the way they thought about disease, its treatment and methods of prevention, some also realising that there were different ways of transmitting the disease, and especially via the air - the stage when a victim's lungs were infected was actually referred to as "pneumonic plague" and, although it would be many years before te medical profession really began to understand everything about infection, the Black Death did at least serve to kick-start the thinking process.

Once the Black Death had passed, there were further problems. In badly affected areas there was a huge shortage of labour and noble estate owners began trying to recruit workers from other manors.

During the Black Death, feudal lords had encouraged peasants to get away from infected areas, but after the disease passed, they often refused to let them return. However the serfs, realising that labour was at a premium, began to demand higher wages, which the lords often had to pay, or risk losing their harvest.

Skilled workers, such as blacksmiths, were in great demand and prices for their work began to spiral. The economy of the country was in a real mess (some things just don't seem to change!) and the government was forced to act, passing the 1351 Statute of Labourers, which staed that no peasants could be paid wages at a higher rate than that which they were receiving in 1346 and no lord could offer to pay a higher rate, in an attempt to draw them away from their original employment.

Many peasants - and indeed, many lords - chose to ignore the statute, even though the penalties if prosecuted and found guilty were high, and the situation remained unstable for years, until eventually it boiled over in the Peasants Revolt of 1381.