A/N: Just a short piece I had in my head that finally demanded to be let out. I edited the ending.
It didn't hit Merlin right away.
For one week after Arthur's…. death, Merlin just sat on the shores of the lake, still trying to grasp the situation. He'd failed, no matter what the dragon had claimed. Arthur was dead.
Albion wasn't. Arthur would want him to continue protecting the kingdom they'd built, would want him to protect their friends.
Merlin could do that. He might not be able to face them, but he could work from the shadows. He was used to that.
He buried Morgana first. Whatever evil she'd done, she deserved a burial. Merlin ignored the guilt. Morgana had turned to Morgause because she'd felt like she was alone, and he had poisoned her. Maybe this wouldn't have happened if he'd been forthright with Morgana and been a friend.
Merlin buried his fear and hesitation alongside the sorceress. He was the strongest magic-user.
He learned of Gwaine's death at Morgana's hand the next day.
For the next five years, he made sure battles stayed in Camelot's direction. He stopped assassination plans. Merlin noticed that his looks hadn't changed since Arthur's death, but he didn't think much of it.
Gaius died the next year of old age. Merlin hid in the back of the funeral procession and mourned the man he considered a father, but he channeled his grief into protecting Camelot better.
Leon died three years after that.
Percy died seven years later. Merlin still looked like a twenty year old man.
Their deaths hit him hard, but he persevered. He had a mission: protect Albion.
He almost broke when Hunith died, but she went peacefully, in her sleep.
He faltered when Gwen died fourteen years later. The woman Arthur had loved and treasured above all others. She had given Camelot a long and prosperous era, but now his family was dead. Merlin staggered into the magic cave where he'd regained his magic and sealed the entrance behind him.
For the next three years, he slept.
When he awoke, he provided assistance to Albion until the despair and loneliness grew so great that he needed to sleep again.
His time awake grew shorter and shorter as his sleeping periods grew longer and longer. Five years, twelve years, thirty years, fifty years, two hundred years….
Once, he tried to create a family, but he had a duty to Arthur and Albion. Arthur… His best friend, his King, his other half.
Merlin met interesting people. William Wallace, William Shakespeare, Winston Churchill, Queen Elizabeth I, King Richard the Lionheart. Lionheart.
There were several wars, each one worse than the previous. Magic and the Old Religion faded from people's memories and became a myth. Humanity's knowledge increased.
Soon it was two thousand years since Arthur's death. Two thousand years? Three thousand? Time became meaningless.
Merlin, still with the appearance of a twenty year old, only awoke when Albion- England? United Kingdom?- was in trouble, his magic alerting him, intent on keeping his vow to protect the land no matter what happened.
He had no one, only a faint promise and a diminishing hope that one day Arthur would return.