AN: So basically this series is inspired by a quote used to describe the dance between Hotch and Emily at the end of Season 7 as a nod to pretty much what could have happened between them, maybe in another life. Also I just needed an excuse to try writing a range of historical AUs. I hope you like them.

Rome – 74AD

The sun shone over the cloudless azure sky. It was nearing the summer and in Rome, the streets were filled with people going about their daily business. Stalls and vendors were selling their wares; their yells mixing in with the shrieks of delight of playing children, revelling in a holiday from school. Mothers and daughters moved through the marketplace as men and sons walked towards the centre of the action. Today a brave legion of soldiers were returning, triumphant and victorious in battle against the Celts in Gaul and Britannia and the Emperor had proclaimed today to be a celebration. The gods had blessed their brave soldiers, granting them victory in battle. The great city of Rome was alive and vibrant in celebration of their victories. Tonight there would be even more celebrations, drinking, dancing, music and laughter but today, people of all ranks, even slaves were permitted to celebrate the victory of the greatest army on Earth.

In their family's villa, Emilia, daughter of the senator Remus, could hear the sounds of people in the streets. Today was an important day; not just because of their victory but also because today, soldiers who had completed their twenty five years of duty in the Army would be formally retired from service. They would be gifted with gold and land, depending on their rank and service as well as be permitted to live a civilian life; a peaceful life compared to the constant trials and dangers of war.

It was also the day he was coming back for her.

"You're betrothed?" Aaron asked her as they sat together in her father's atrium. Emilia brushed a strand of hair from her forehead and nodded; her gaze falling on her golden betrothal ring on her finger.

"His name is Matthias. We're the same age and his father is a Senator with my father." Emilia explained. She was fourteen, almost fifteen. It was time for her to marry, really she ought to have been betrothed a few years ago. Many Roman girls were betrothed around the age of ten and married at fourteen. She had met Matthias and believed him to be a good man, a good friend and hopefully a good husband. She just wished she was marrying the man beside her.

"Well, since we're sharing secrets; I need to be honest with you. My father wants me to enlist in the army. I'm twenty so I'm old enough now." Aaron said as Emilia looked at him surprised. She knew Aaron's father had served proudly in the Roman army before an injury sustained in a battle against the Spartans had forced him to leave the army. She just never thought he would make Aaron enlist. Being a Roman soldier meant twenty five years of loyal service; if you survived that long. He could be anywhere within the great Empire; from the borders between Britannia and Caledonia all the way to Egypt or Syria. Most importantly, Roman soldiers were forbidden from marrying or having children until the end of their service. Not that it would matter, now that she was promised to another.

"Do you want to?" Emilia asked and Aaron looked at her. It was only the fact that they were next door neighbours and childhood friends that he was able to confide in her and so, shook his head.

"Not really but consider it from my father's point of view. I was named after him but I choose to be known by my middle name; the name of the Hebrew physician who helped bring me into this world. We argue constantly, he feels I disrespect him. If I do this, I will be a good son and respect his wishes." Aaron replied. His real name was Claudius Aaron Herminius but his bad relationship with his father had made him rebel. Now that he was getting older; he wanted to do right by his father. Besides, his father still had a say in who he married. Not that it mattered, considering the woman he wanted to marry was now betrothed.

"But you'll be gone for so long." Emilia said and Aaron nodded.

"Twenty five years." Aaron said and looked at Emilia. He would be honoured to serve the Roman Empire, he also wished he could follow his heart. But it seemed the gods had different plans for them. "When will you be married?"

"Within a few weeks. When will you have to leave to begin training?" Emily asked and Aaron looked at her sadly.

"Within a few weeks." Aaron permitted and they fell into silence. There was a time when they would laugh and shriek and play; but that was childhood. They were adults now and had to accept the paths chosen for them to follow.

Emilia's marriage to Matthias had been a good one. He had been a loving and kind husband who worked hard to provide for them. Although their marriage had never bourne fruit; he never blamed her or sought to divorce her like many other Roman men would do; they were entitled to by law after all. Instead, he had remained a faithful husband and even when he became deadly ill, never left her side and hated to see her upset. On the night he died, Matthias had made her promise two things. The first was that she try and find happiness again, wherever it would be. The second was that she never gave up on love; that if she ever was promised to another or loved another; that she never deny her heart happiness and love. Although she was unable to inherit anything after his death; there were times when she despised Roman law, Emilia had the promises she had made.

It had taken a year for her to sum up the courage to even consider writing to Aaron. She knew he was alive; his father had passed from illness not long after he had enlisted, but his mother Julia still received letters from him. Even when she had the tools to write, doubts plagued her mind. Would he want to hear from her? Would he write back to her? Did he even remember her? One night, she didn't restrict herself anymore and began to write to him. It took a few months for him to reply but he had.

That was when their correspondence had begun. Emilia told him of her marriage and widowhood and life in Rome. Aaron replied with news about life in the army. How he had risen between the ranks, some of the battles they had faced and won and as the years passed; his retirement from the army. They both knew what his retirement meant. Land and gold and maybe servants but most importantly; freedom to marry. His last letter had come a week prior, confirming that he would be coming home, indeed, he was already on his way. Emilia hadn't been the only one to make and keep a promise; Aaron had too.

"This is for you." Aaron said as he gently placed the bracelet around her wrist. It was delicate and silver and looked expensive. Emilia looked at the bracelet and looked at him.

"It's beautiful." Emilia said; it had been a few weeks since they had shared the news of their fates. Tonight was also Aaron's last night at home before he left to begin his army training and it was four days until her marriage to Matthias.

"Consider it a promise. My promise that I will return to you. The gods shall be good and bless us both. I don't know how long it will take and I will not wish an unhappy marriage on you. Just know that someday, we will have a chance." Aaron said as Emilia took his hand in hers. They had no idea what the future held. Only the gods knew that and right now their fates were not looking good. He was about to leave for twenty five years of war; she was promised to be another's bride. Then again maybe this was all part of the gods' plan for them.

"I have something for you too." Emilia said as she looked at Aaron. She was promised to another, due to marry in four days' time but she also might never see the man who first won her heart; her first love, ever again. It was the one gift she could give him, one gift that nobody, especially not her father or future husband would ever know about. One gift she could give him that he could take with him wherever he went. Her husband would have her maidenhead but Aaron would have her first kiss.

As Emilia stepped closer to Aaron, he suddenly realised what she was going to do. Part of him knew it was wrong, kissing a woman who was about to be wed would be considered adultery. They could be executed for it. However he found that he didn't care. If nobody ever knew, they wouldn't be in trouble. And he knew he could possibly never see her again and she was his first love. Aaron closed his eyes as their lips met and the rest of the world disappeared. They were no longer a betrothed woman and a man heading for war; they were two young lovers mourning what could have been.

"I should go." Aaron whispered as they broke apart. Emilia blinked back the sudden tears in her eyes and braved a smile.

"You better come back for me. Otherwise I'll go to the underworld myself and demand that Pluto himself return you to me." Emilia claimed and Aaron laughed. He had no doubt that she would.

"Emilia."

Emilia turned at the voice to see her mother Elizabeth enter the room. There was a knowing smile on her face as she looked at her daughter. "There's someone here to see you."

Careful not to seem wanton, Emily carefully moved away from her window and traced a finger over her bracelet. As she followed her mother through the villa towards the atrium, she knew what this had to be about. There was only one person who would come to see her today. The official ceremony had been this morning and he would be here by now. As they walked into the atrium, Emilia saw her father standing nearby but her attention was now distracted by the man who was standing by the fountain in the middle.

He was taller than she remembered, his shoulders broad and strong, dressed in a new, expensive toga. There were a few lines on his face and the frown on his face had clearly been ingrained through years of war, training and discipline. However as he looked at her with familiar, warm brown eyes, his face broke into a warm loving smile. As they looked at one another, suddenly they were no longer adults; they were young and carefree and madly in love. Forgetting all manners and decorum, Emilia rushed across the atrium and into Aaron's arms, almost sending them toppling backwards as they hugged and laughed.

"I knew you would come back," Emilia said as she reached up and cupped his cheek with her hand. Aaron's gaze fell on the bracelet around her wrist. She had kept it; even after all these years, she had kept the bracelet he had given her as a promise of his return.

"I told you I would." Aaron said as he reached into his pocket. Emilia had not been the only member of her family he had been in correspondence with. Once he knew this was what they wanted, he had written to her father and helped to arrange everything. Her father Remus had even found a ring for her. Emilia's eyes widened at the sight of the ring; it was a simple gold ring with two joined hands engraved onto it. She had only received a ring like it once before.

"Aaron," Emilia said as Aaron smiled at her.

"I asked your father for your hand in marriage." Even after all this time, he had wanted to maintain the formalities and ensure both their families would be welcoming of this match. It was a moment they had both waited years for Venus to bless them with. "Will you accept?"

"Of course I will!" Emilia said as Aaron slipped the ring onto her finger. In the same spot, twenty five years prior where Aaron had gifted her with an important piece of jewellery, she returned his gift with a kiss. A kiss this time, he had no hesitation in accepting. They both hoped they would be married soon; after all, they had already waited twenty five years for this day.