‘I hope I don’t disappoint,’ Orm growled ungraciously. In the bright Spanish sunlight he was massive, heavy, somehow dark, Robert thought. He wasn’t comfortable here. And his head probably hurt from the monkish wine he and Sihtric had consumed the night before. Orm said to Robert, ‘Don’t you notice anything different about me today?’

‘By God’s eyes. You cut your hair.’

He stroked his chin. ‘Look, a good shave too. And I had a bath.’

Robert was genuinely shocked. ‘You didn’t.’

‘I went to one of those bathhouses the Moors have. Quite pleasant it was, if you can put up with smelling like an East Roman whore.’

Ibn Hafsun smiled. ‘You have to make yourself presentable to meet a Muslim ruler. Clean clothes, a wash. The envoys of the Christian kings, even of the Pope, have always known this. Of course Christians aren’t quite as in awe of the Moors as they were in my father’s day.’

Moraima, serving more wine, passed Robert. ‘I’m glad you haven’t bathed. I quite like the way Christians smell.’ And with a fleeting, luring smile, she turned away.

Sihtric lectured them about Cordoba’s magnificence. ‘At its peak, only a generation ago, it was the greatest city in the west. Why, its population even matched Constantinople. Five hundred mosques. Three hundred bathhouses. Fifty hospitals. Do you even know what a “hospital” is, young Robert?

‘And the greatest library in all the world, it is said, flourished here in Cordoba, under the caliphs. It all started when the East Roman emperor sent the caliph a copy of a pharmacology text by Dioscorides - have you heard of him? It was like dropping a bit of hot iron into a pan of water. Scholarship boiled in al-Andalus . . .’

The caliphs, rich and at peace, embraced learning as an emblem of power and sophistication. And they were much better placed to do so than western Christendom, for they had access to the surviving works of antiquity. Employing legions of copyists and translators, the Moorish scholars merged Greek and Roman learning with what their cousins in Damascus and Baghdad had acquired from the Persians, and they built on what they learned. The result was a flowering in astronomy and physics, medicine and philosophy.

Sihtric said, ‘The library itself grew to four hundred thousand books. The catalogue alone ran to forty-four volumes! This was at a time when the kings of England were entirely illiterate. But when the caliphate fell the library was broken up. How I wish I had been born a generation earlier. But there are still books milling around the city, as if released into the wild. It is my skill at tracking the books down as much as my learning that makes me so useful to Ibn Tufayl, I think . . .’

Sihtric was a man of contradictions. For all his admiration of Cordoba’s Moorish achievements, he was keen to play up its deeper Roman origins.