That the commander turned out to be a wiry, compact, elegant ruffian who was also a cardinal amused her and stimulated her the more.

`Where will you go from here?' he asked.

'I go with you, my lord, to aid in your conquest.'

He put his hands into her bodice and lifted out her breasts. Better our conquest than anyone's, dear lady,' he said.

Cossa left a token force at the gates of Bologna to remind the

occupying Milanese troops that their work: was: over. He rode through the cities between Bologna and Milan taking cheers. A peace was written with the Council of Milan. The pope instructed Cossa not to include his allies, the Florentines, in the peace, although they had expended 80;000 florins on the war, because he had learned that `a Florentine bank' had financed Gian Galeazzo in making the war, and also he did not wish to share Cossa's loot and ransom money with them. Despite this betrayal, the Florentines showed no rancour towards Cossa, because the Marchesa di Artegiana had confirmed to Cosimo di Medici that she saw qualities in Cossa which could be fortunate for the bank, so Giovanni di Bicci di Medici extolled Cossa eloquently in his speech before the Signoria of Florence.

Cossa was besotted with the marchesa. I had seen him almost as insanely affected years before, when we had left the red-haired woman on the bed in Perugia and I had made him ride on to Rome; but he was older now and, after the stint at the Vatican, a far more worldly man, who, anyone would have thought, should have been less paralytically susceptible than the marchesa had revealed him to be. He wanted her at his side at all times. He could not keep his hands off her. He could stare at her for embarrassingly long, moments, as a hen stares at a white chalk line on the ground. He heaped jewels on her. When the temperature dropped, he ordered furs to be brought for her. He was on her and in her like an unbalanced satyr, moaning, talking brokenly. I must have lost two hours' sleep every night because of the noises he made on that woman.

He told me he thought sometimes that he was two people. One of these was pulled helplessly into the orbit of the woman from Perugia the other knew he belonged to the marchesa for ever. `I still think of that woman whom we left in Perugia, Franco,' he said to me. `Never a day or a night has passed when she has not been vividly in my mind. Even when I am upon the marchesa and almost frantic with the love of her, I think of the woman, whom I left in Perugia. She is with me now. She will probably always be a part of me and I rejoice at that, but the woman who commands my soul is the Marchesa di Artegiana. She consumes me. She is in my mind and in my bones and yet – even I know that she is but one of the two women in my life. I will never see her again that woman in Perugia, but she lives for me while the marchesa blinds me like a sun.'

`It could be worse,' I said.

`How could it be worse?'

'Well- it could be four women. Or ten. But at some point; you would have to start to lose track.'

He glared at me. `How would you like me to have Palo cut your balls off?' he snapped.

When Cardinal Cossa had concluded the papal treaty with the Milan Council and was alone in the command tent outside Milan's walls, Carlo Malatesta spoke to him. Malatesta was one of Cossa's generals, called `the best and most loyal of his race’, a man who was married to a daughter of Bernabo Visconti; making him a brotherin-law of the late Gian Galeazzo Visconti, Duke of Milan. Cossa had respect for Malatesta as well as affection. They greeted each other warmly and to honour the day, Cossa bade him sit and drink a glass of wine.

`What brings you here?' Cossa asked. `I am happy to see you always.'

`Your, Eminence – there is a matter – that is, you may know that my wife's sister is, Catherine Visconti, widow of Gian' Galeazzo.' Cossa nodded.

`She has asked me to ask you for an audience with her. She is a sensible woman – after all, she is a Visconti – so there is no possibility of embarrassment for, you. And may I also say that Francesco de Gonzaga, Lord of Mantua, a member of the council with whom you have just made the treaty, who is married to yet another sister of Catherine Visconti – there are nine in all – adds his own petition to mine that you grant this request.'

'My dear fellow! Of course. I would be honoured to meet, such a great lady.'

`Then she will come to your tent tonight, Eminence.'

`Out of the question. That would be intolerable. I will, of course, go to her.'

Malatesta cleared his throat. `That would be indelicate, Eminence. As you have just concluded a treaty with Milan without conquering it, the Milanese would' be offended if you entered the city:

`Nonetheless,' the cardinal said, `I did conquer the Milanese, and I will not permit the widow of a great man to be humiliated by having to come through a military camp to see me. Please – you yourself, and Gonzaga as well if he wishes, will escort me via some little-used way into the city and take me to where the lady waits. I will dress myself in the Milanese style. No one will notice me.'

`The duchess wishes to meet you alone, Eminence. I will send you Gonzaga's own man to take you to her.'

When Malatesta had gone, Cossa asked me what I thought it was all about. `It sounds a lot like she wants to get laid,'' I said. 'New widows are like that.'

The following night, three hours after darkness fell, Cossa's guide came to the tent and I searched him for weapons. While the cardinal general, dressed as a civilian, rode with the man towards the city walls, I followed them silently.

When they reached a secondary gate, I caught up and the three of us were allowed by the guard to pass through. The streets had been emptied by curfew.

`She is in the citadel,' the guide told us. We reached the door of the high, windowless tower and Cossa dismounted. I secured his horse and settled down to wait.

The man unlocked the door. Cossa went inside. When he returned four hours later, he was an utterly different man. He was very pale as if he had slept with giant bats who had drained him of blood. He appeared to me to be about fifty pounds lighter and he wore a silly coltish grin. He told me what had happened:

Inside the tower he had faced a spiral staircase ascending into darkness. He climbed the stairs. A few minutes before he reached the top, a door opened above him and the light fell upon him. He kept climbing and entered the open door, closing it behind him.

Before him, in serene repose, sat the delicately ravenous woman who had occupied his mind since the night in Perugia when he had been an archdeacon and she had seduced him, the woman for whom he had searched until the Marchesa di Artegiana had distracted him from the dream. He reached out for her as if he were stretching out to grasp an apparition. She was solidly real.

Long after, while she lay in his arms, she sleepily told him her story. In 1380; when she was twelve years old, her father, Bernabo Visconti, had compelled Gian Galeazzo to marry her, hoping in this way to neutralize his rival. She lived with the duke, her first cousin; at the ducal palace in Pavia, the great fortress-palace which his father had built into the north wall of the city. Although her husband was a stranger to honour, she said, he was devoted to art and scholarship. He was secretive: He loved the silent gardens and the woods that stretched away on the other side of the Ticino. He was already a widower but he had had to put away his private grief because having no male heir gave temptation to his rivals. Before he and Catherine were married, Gian Galeazzo had been negotiating a secret betrothal to a Sicilian princess, which would have strengthened his position against Bernabo Visconti. But Bernabo made sure that wedding did not take place. After his marriage to Catherine, Gian Galeazzo was completely at Bernabo's mercy and Bernabo had little mercy.