Eventually, they came to a great council chamber lined with arches. Two chairs were set upon a marble dais, one for Manuel, one for Louis. Everyone else was expected to remain standing, Alienor and Irene included.

An interpreter with a curled and oiled beard stood ready between the King and Emperor, for although Louis spoke Latin, Manuel did not. The conversation between the sovereigns was as elaborate as the surrounding architecture and decoration, for while Louis’s responses were terse, the interpreter embellished his words with the flowery speech and mannerisms of the Greek court. Listening to Louis’s replies, Alienor understood that opening pleasantries were being exchanged. In the Greek way, there would be no serious discussion today, tomorrow, or even the day after.

Preliminaries concluded, she and Louis were escorted to dine with the Emperor and his court in another chamber, once more reached through painted corridors with shining marble floors. The dining tables were marble too, pink and cream, ornately carved and draped with white napery. Fragrances of rose water, cinnamon and nutmeg permeated the sumptuous dishes, served on plates of ceramic and silver gilt. There was tender lamb with apricot sauce, crisp golden game birds stuffed with wild rice, and platters of glittering silver fish from the rich waters of the Golden Horn.

The Greeks ate their food with a two-pronged implement that speared the pieces of lamb or apricot and held them securely to be dipped in piquant sauces, or in olive oil, pale green as liquid glass. Seeing Alienor’s interest, Irene presented Alienor with her own as a gift. ‘You will soon wonder how you ever managed without one of these,’ she said.

Alienor thanked her and admired the ivory handle inlaid with small squares of iridescent mosaic.

‘You must see the great sights of our city while you are here,’ Irene added. ‘I will show you myself, and we can become better acquainted.’

‘I should like that; you are most gracious,’ Alienor replied, smiling.

Irene returned the smile, although the curve of her lips was not echoed by her eyes, which were deep and watchful. ‘Your husband: he has the reputation amongst us already for being a pious man. We hear from our merchants that he spends much of his time in prayer.’

‘That is so.’ Alienor lifted her cup, thinking that ‘merchants’ was a euphemism for ‘spies’. ‘My husband was trained for the priesthood as a child before he became the heir to the throne.’

‘He will find much to inspire him in our city. We have churches, shrines and relics of value beyond price that the emperors have guarded and protected from enemies for a thousand years. Long may they continue to do so.’

Alienor did not miss the warning and challenge in Irene’s seemingly bland words. Louis was welcome to look, but not to touch, and the French were not so much allies as an expedient way of distracting Constantinople’s enemies. ‘I believe we have a great deal to learn from each other,’ Alienor said.

‘Indeed,’ Irene replied smoothly, lifting her own cup. ‘Just so.’

Alienor settled into life in Constantinople. The opulence was seductive. She, Louis and their retinues were housed in a hunting lodge that made Talmont look like a peasant’s hovel by comparison. On the first night, Alienor bathed away the aches of the long journey in hot water scented with rose petals. Attendants rubbed her body with exotic oils and massaged out the knots and pains of travelling until she felt light-headed and languorous. The Emperor provided them with servants in addition to their own to wait upon their every need.

‘Spies,’ Louis said, his nostrils flaring as he pushed aside a platter of small almond cakes decorated with coloured sugar. ‘They set spies on us, and we cannot do the same to them.’

Alienor shrugged. ‘What are they going to find out?’

‘Nothing, because we will tell them nothing.’ He caught her wrist as she walked past him and pulled her to face him. ‘I do not want you talking to the Empress and giving things away, do you hear? I know what gossips women are.’

‘I am not a fool,’ she retorted. ‘The Empress and I understand each other well.’ She wrenched herself free, rubbing the place where his fingers had dug in. ‘You should be encouraging me to talk to her and probe for information, but you do not want me to have that kind of power, do you?’

‘This is men’s business. You will not meddle.’

She set her jaw.

‘I am warning you.’ He wagged his forefinger in front of her face. ‘I will not brook plotting of any kind.’

‘It does not occur to you that I might be trying to help you?’

‘No,’ he said. ‘It doesn’t.’ He stamped from the room and across the corridor to his own chamber. Thierry de Galeran was standing on guard outside it, and he gave Alienor a knowing smirk. She rubbed her wrist where Louis had seized her, and her irritation at his stupidity churned into anger. The Greeks would swiftly know from their spies that the King and Queen of the Franks were not in accord. What point was there in ordering her to be careful when his own actions left the door wide open to all?

The opulence and luxury of Constantinople continued to take Alienor’s breath away. At sunrise and sunset the city shone, every surface lustrous with gilt and bronze and gold. Irene took her to the roof of the Blachernae Palace and, on a glorious day of white sunshine and soft breezes, pointed out to Alienor the hippodrome, the forums of Emperor Constantine and Theodosius, the cathedral of Saint Sophia. Across the river the quarters of the Genoese traders at Galata shone like a separate golden casket. Irene spoke rapidly and she indicated everything with swift movements, as if determined to fulfil her duties as hostess by leaving nothing out.

Constantinople in the flesh was exhausting. Whisked all over the city by their hosts and shown one astonishing site after another, Alienor found them becoming an amorphous blur of crystal, marble and gold. It was almost like being drugged, or smothered, and for all its beauty the city was intensely claustrophobic. Louis spent hours worshipping at jewelled shrines beside which the church of Saint-Denis paled into insignificance.

The French army was forced to remain outside the defensive walls under canvas and only permitted through the gates in strictly controlled small numbers. The Emperor was not about to let a mob loose in his city. The soldiers’ experience of Constantinople was different to that of their liege lord and lady for they saw the parts that Louis and Alienor did not, yet it was just as edifying. The troops experienced the stinking, fetid underworld of the poor, riddled with disease and thievery. In the dark, narrow streets in the bowels of the greatest city in Christendom, where even full daylight was dim at ground level, the denizens lived a squalid, subterranean life. Pilgrims and soldiers reported back to their fellows that the city resembled an enormous golden stone turned over to reveal the mud and wriggling creatures underneath, and, by comparison, even the dankest, most unpleasant parts of Paris were places of high illumination.

A fortnight passed and Louis continued to wait for the arrival of the part of his army that had travelled by a different route. The feast of Saint Denis fell on the eve of that arrival and the Emperor sent Louis a select group of clergy to sing the service in celebration of the saint. Each monk was furnished with a tall taper elaborately decorated with gold leaf and vivid colours. There were eunuchs among the Greeks, castrated before their voices had broken. Their bodies were soft and plump and they sang in sweet high tones that blended with the deeper resonance of the other men, and the wonderful sounds brought Louis to tears.

Alienor wondered at the purpose of this musical gift, because she knew the Greeks were too wily to give anything purely for itself, even if they too celebrated the feast of Saint Denis in their calendar. Nevertheless, the service was beautiful and she thanked Irene graciously.

The Empress smiled and arranged the drape of her dalmatic on her sleeve so that the gold edge fell in a precisely straight line. They were seated in one of Irene’s many chambers at the Blachernae Palace with glorious views of the Golden Horn through the open windows. Servants had come on quiet feet to pour sweet wine and serve delicate rose-water pastries. ‘The Emperor and I have done our best to make you welcome in our land, and we felt that it was a fitting culmination.’

Alienor picked up on the last word. She reached to the delicate glass cup on the mosaic-inlaid table. ‘Culmination?’

Irene waved a smooth, manicured hand. ‘Naturally once your contingent from Italy has arrived, you will want to continue your journey.’

‘Indeed,’ Alienor said. ‘But our companions will need to rest before we set out.’

Irene inclined her head. ‘We are happy to welcome them while we make ready boats and supplies. However, your kin in Antioch must be anxiously awaiting your arrival.’ She affected a concerned expression.

So the Emperor wanted them gone, Alienor thought, and the celebratory service for Saint Denis was a punctuation mark on their stay. ‘My uncle will be glad to receive us,’ she replied, ‘but he understands the dangers of our journey and he would want us to set out well prepared and in strength.’

‘Indeed, but you should leave before the winter sets in.’ Irene leaned towards her as if speaking in confidence. ‘My husband hears reports that the German army has defeated all resistance it has met thus far. There has been a battle and thousands of Turks have been killed. Your way will be clear if you follow now.’

Alienor was surprised. ‘That is news I have not heard.’

Irene looked smug. ‘Indeed not. The messenger has not long returned with the tidings. The Emperor will send word to your husband this very day.’