What were the crusades? Your top questions answered

There are many other non-religious motivations, such as the charismatic preaching that we see happening with these crusades. Take a figure like Bernard of Clairvaux on the Second Crusade. He preaches all over Europe drawing large crowds, and influences kings to ‘take the cross’: Louis VII, Conrad III.

I think crusaders were also spurred on by the idea of the deeds of their ancestors, the glory that can pertain to their families if they take part in these great expeditions. Certainly, kings and emperors think it will do their ‘PR’ no harm. They take the cross often when they become kings. Often, it's a way of showing that there is a new reign and that they’re different from their fathers.

There's no doubt that there were also ideas of adventure. At the time of the First Crusade, there had been very bad harvests; there was famine in Europe, so people wanted something different and new. Of course, when they get out there, they didn't necessarily like it. But there were all kinds of romantic and adventurous ideas associated with the crusades.

Then there were the economic ideas. But an individual crusader doesn't just have to have one motivation. He can be conventionally very pious. He can also be hoping to be in favour with his lord. He can be hoping that there might be some land parcelled out to him. He can be inspired by charismatic preaching. He is an individual. These days in the historiography, historians do try and show that mixed motivation. And I think that's important. Religious, political, social, economic motivations all play their part.

How many crusades were there?

This is very debated by historians writing about the crusades today. For me, there are eight crusades during the period from 1095 to 1291 in the Near East (so not crusading within Europe).

If I run through them very quickly: The First Crusade (1095–99), where the crusaders take Jerusalem and set up the crusader states. The Second Crusade (1147–50), which is a response to the fall of the first crusader kingdom of Edessa (the crusader kingdom in the north). The Third Crusade (1189–92) is launched to try to win back Jerusalem and, of course, is perhaps the most famous one for us, because we think about Richard the Lionheart. The Fourth Crusade (1202–04) doesn't end up in the Holy Land at all, but the crusaders instead sack the town of Zara and then Constantinople, very famously. The Fifth Crusade (1217–21) is an attack that the crusaders make on Egypt, on the town of Damietta in particular (and this ends in failure). The Sixth Crusade (1228–29) is very interesting because it's not authorised by the papacy, but it’s a crusade where an emperor, namely Frederick II, goes out under excommunication. He has a lot of success and makes a truce with the sultan and gets Jerusalem back for 10 years. Finally, I like to think of the Seventh (1248–54) and Eighth (1270) Crusades, which are the two crusades of Louis IX, launched respectively at Egypt and at Tunis.

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But let's not forget that there were also many more minor expeditions. People were taking a passage out to the east: there were small groups of fighters between these major crusades as well. So we can think of the Barons’ crusade of 1236, for example, or the crusade right at the end of our period, by Edward, prince of England, sometimes called the Ninth Crusade (1271–72). These little ventures are going on between these major responses. (And by major responses, I'm talking about great papal calls being put out there, and very large armies then taking up that call and going out to the east.)

How did the crusades end?

The crusades ended when the Mamluks (one particular Muslim group) captured Acre in 1291.

For decades, Acre had been the centre of what remained of the kingdom of Jerusalem – and so it was the most important city that was still left of the crusader states. It fell to the Mamluk Sultan Khalil in 1291. In the days that followed, the rest of the remaining crusader towns – Beirut, Haifa, Tyre, Tortosa – all fell in a domino effect. This happened in 1291, the end of Outremer, as they called it, the end of the land across the sea.

Who won the crusades?

A: As we know, the crusader states were lost. The final bastions of the crusader states were lost in 1291 (having been founded originally in 1099) to Muslim forces. In that sense, obviously the Muslims won the crusades and the Christians were defeated.

However, the crusades span a very long period of time, starting with the First Crusade in 1095 and ending with the loss of Acre in 1291. There were many individual crusades within that period, some of which were won by the Christians – by the Western Franks, like the First Crusade – and others by Muslims. For example, the Muslim forces were successful in the Fifth Crusade in capturing Damietta.

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And then in some crusades, we have partial victories. If we take the Third Crusade, Richard the Lionheart was partially successful, in the sense that he was able to take and maintain Acre. But, of course, he didn't win back Jerusalem with a military victory.

Overall, the answer to the question is: the Muslims won and the Christians lost. But we need to look at individual crusades and see how each one pans out. We can look at particular battles and sieges and try to evaluate within each crusade who comes out as victorious.

How many died in the crusades?

I should give a caveat here: it is very difficult to estimate because of our source material. Medieval chroniclers are notoriously unreliable when they give figures of battles and losses. Other types of evidence – for example charter evidence – may help to give us a better picture. Nevertheless, we're dealing with very unreliable sources. As I've also already said, some of the crusades are big expeditions and others much smaller. These factors need to be taken into account when we try and make estimates.

There are figures ranging from 1 million to 9 million over the whole period from 1095 to 1291. John Robertson famously, in his Short History of Christianity – a very old but seminal book first published in the early 20th century – had that really huge figure of 9 million. But I've seen other historians estimate much lower numbers. When I'm giving these figures, I'm including Christians, Muslims and all those who followed the armies, not just the combatants. So, yes, there are estimated figures within the historiography, everything between 1 million and 9 million.

Because historians regard it as so difficult to try to get any accurate figures, they prefer in general – and certainly in the recent historiography – to try to give estimates for individual battles rather than for a crusade overall. And I think that gives us a better sense of what's going on – the carnage, the losses.

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For example, historians these days tend to think that in the princes' element of the First Crusade, when they set out after they've heard Urban II's speech at Clermont, there were probably 70-80,000 people who took part in that expedition. Maybe some more joined en route, but it’s those kinds of numbers.

Certainly the estimate of one million deaths seems far too few to me

Then, when historians look at the fall of Jerusalem to the Christians in 1099, they estimate that somewhere between 700 and 3,000 people were actually killed by the crusaders in Jerusalem. I'd probably go for the higher end of that. Sometimes I think those kinds of figures are more helpful.

Regarding the overall estimates between 1 million and 9 million, certainly one million seems far too few to me. I would go for a much higher figure: 5 or 6 million.

These answers are taken from a podcast episode with Professor Rebecca Rist of the University of Reading, who took on questions submitted by readers and the top queries posed to the internet about the crusades. Please note that minor edits have been made for clarity, the full episode is available now: The crusades: everything you wanted to know