Brasus could see no sign of a trap, and revealing his own presence did not betray his men. He leaned forward out of the window and shouted down. ‘Friend!’

The cavalryman started at the reply, having probably decided that the tower was empty. Brasus gestured to him. ‘Dismount and come in! Slowly!’ Whether or not he understood the words the Gaul or whoever he was saw the beckoning arm. He swung down from his horse, dropped his shield to lie by the sword and walked up the rubble, arms spread wide to show that they were empty and that he was no threat.

‘Call the other!’ Brasus pointed at the distant rider and beckoned again. The man nodded, and shouted something back at his comrade, who came on. Then he gasped as warriors appeared on either side of him.

‘Just watch him!’ Brasus shouted to his men. ‘And wait for me.’

By the time he had come down the second cavalryman had come in. One of the warriors held their horses while the rest watched the prisoners.

‘Says his name is Ivonercus and this is his servant,’ the oldest of the warriors told him. He spoke the Celtic language and they had managed to communicate a little. ‘They’re both Britons and have run from the Roman army.’

‘Why have you come?’ Brasus asked in Latin.

‘To serve Decebalus,’ Ivonercus told him. ‘And to fight for him.’

The king always welcomed deserters. If their story was true then they would be taken into his service, but that was for another day. For the moment he explained that they were prisoners and would be guarded until they crossed back through the pass and reached safety. Only then – if they answered all questions satisfactorily – would they be given back their weapons.

‘I understand,’ Ivonercus assured him. The man seemed desperate to please.

‘Take them there,’ Brasus ordered, pointing at one of the out-buildings that still had most of its roof, ‘and guard them. Bring their horses inside so that they cannot be seen.’

‘Yes, my lord.’ The older warrior did not say anymore, but the question was obvious from his expression.

‘We will wait another day for the messenger. Perhaps two if nothing else seems wrong.’ Brasus smiled. ‘One man watches the prisoners and another on guard – in the tower during daylight. There won’t be a lot of sleep.’

‘Two awake, two resting,’ the old warrior said. ‘It could be worse.’

‘There are five of us, and I shall take my turn like everyone else.’

‘My lord.’

V

Rome

Tenth day before the Kalends of Martias

‘PLEASE, MY LORD, read this!’ The old woman thrust a writing tablet out in her right hand, while her left elbow jabbed into a man trying to push her out of the way to present his own petition. For all her grey hairs, she was plump and powerful, and the victim dropped his rolled papyrus as he doubled over. One of the toga-clad praetorians scooped to pick the scroll up and then took the woman’s tablet as well. Other guardsmen in cloaks and tunics, but carrying big oval shields and pila, formed a cordon to mark the line beyond which the crowd was not permitted. A good princeps ought to be accessible, so like the divine Augustus, Trajan walked whenever possible, even on occasions like this when he was to dine at a friend’s house, itself another mark that he was servant of the res publica and not a tyrant. The journey was unannounced, a social call rather than for some ceremony or to attend a session of the Senate, so the crowd was not as big as on other days. These petitioners were only the ones who had waited hour after hour and sometimes day after day outside the main doors of the Domus Tiberiana, the house of the princeps, on the off-chance that he would appear.