L.M.
Your boy might be getting to that point where he is out-growing his nap time. Try one day with no nap, let him run around like crazy an hour or two before bed time (avoid any sugar snacks/juice) - the fresh air and sun might get him tired quicker..
So, - try:-
No nap
Activities two hours outside before bed
A warm bath, bubbles or not
cup of warm milk
- if he likes that, you could put a drop of vanilla essence for flavor or just a little bit of nesquick
Bed at 8pm
Bed time story till 8:15, followed by hugs and kisses.
Lights out by 8:30 (use a timed nightlight)
I got my son a Homedics Sound Spa Lullaby/Nightlight (Target http://www.target.com/gp/detail.html/176-###-###-####-###...) that has a timer. I can set it to 15 min/30 min/45 min or an hour. When its lights out he usually gets the message and goes to sleep.
You could also try and change his room up a bit. Get some cool wall stickers of his fav character and a bed time toy that he can only play with when he is in bed. Something like a Scout plush puppy that sings lullabyes and tell him Scout is there to keep him safe at night. Remind him that you will come in and "tuck him in" when he goes to sleep, kiss him and tell him that you love him.
Kids who feel more assured at bed time, usually goes to sleep easier.
He is asking you to rub his back, because he wants the closeness/affection. If you tell him, kiss him and hug him tight after bed time story, I am sure he will feel more at ease.
Good luck!!