I think this song is all about death.
That is, "The Unknown" - what comes after death?
The singer is singing to the person he has lost in life, and how he will meet them again in the after life, when he dies.
"After the people and places are gone" are the people and places of this world. Once they are gone, that is, once the singer dies, "You will come back to me" he will reunite with his family.
"Sooner or later it all comes around" - death is inevitable. The singer acknowledges this. But in my view, he is not afraid to die.
I think this song is all about death. That is, "The Unknown" - what comes after death? The singer is singing to the person he has lost in life, and how he will meet them again in the after life, when he dies. "After the people and places are gone" are the people and places of this world. Once they are gone, that is, once the singer dies, "You will come back to me" he will reunite with his family.
"Sooner or later it all comes around" - death is inevitable. The singer acknowledges this. But in my view, he is not afraid to die.