He's probably going through a sleep regression, teething and about to do a new trick, more talking or whatever all at once.
I think you mentioned he has been a bad sleeper since birth. I would highly recommend seeing an Osteopath as soon as possible so this can be more resolved before the next one comes along. He may simply need a cranial sacral adjustment. Trust me, seeing a cranial sacral person works WONDERS!! In Tucson see Dr. Thersea Cisler.
Here's another idea to try after seeing the cranial sacral person or to try first what ever works for you.
Try a transition type of method. Go in and put him in the crib and then have him lay down. You bend down or sit on a stool and pat the CRIB mattress NOT the child.
He will be able to look at you, which allows him to be less freaked out. DO NOT talk to him. Each time he gets up, stand up and lay him down, then return to patting the mattress. If looking at him while patting the mattress makes him stay awake, then look away. Do this until he falls asleep.
When you do this repeatedly this becomes the way it is, and he will, hopefully fall asleep.
Then as time goes by he should trust, and you can pat the CRIB mattress less and less.
Good Luck, S. from ProActive Parenting, www.proactiveparenting.net