write a historical novel set in Roman Britain with Main Character is last roman legionnaire
Title: The Last Legionnaire of Britannia

It was the year 410 AD, and Roman Britain was on the brink of collapse. The once-mighty empire had retreated from the province, leaving behind only a handful of legionnaires to defend the land against barbarian invaders. Among them was the young and courageous Marcus, the last Roman legionnaire of Britannia.

Marcus had been born and raised in Rome, trained as a soldier from a young age. He had served in many campaigns, and had been posted to Britannia with the Fourteenth Legion when it had been stationed there over a decade ago. Now, he found himself the only survivor of his unit, with a duty to protect the land and its people, even as the empire crumbled around him.

As he watched the enemy advance, Marcus knew he had to act. He rallied the remaining soldiers, gathered the local tribes to his side, and began to fortify the settlements along the frontier. It was a desperate gambit, but the last hope for the survival of Britannia.

As he fought to keep the invaders at bay, Marcus found himself drawn to the local people and their way of life. He befriended a young Druid priestess, named Livia, who helped him understand the ways of the land and its ancient gods. Together, they formed an unlikely alliance, and fought side-by-side against the enemy hordes.

But as the conflict dragged on, Marcus began to question his loyalty to Rome. He had grown to love the land and its people, and he wondered if his duty lay not with the empire, but with those he had come to protect. As he battled his own demons, Marcus realized that he was not just fighting for survival, but for his own identity and sense of purpose.

The Last Legionnaire of Britannia is a tale of heroism, sacrifice, and the struggle for identity in a time of chaos and uncertainty. It is a story of one man's journey to find his place in a world that was rapidly changing, and the enduring spirit of the people who refused to be conquered.