The Old English Negative Form, Nay

Not still takes its place behind the initial verb, do. And in other verb phrases, it also follows the initial verb. So, am not going, is not here. Will not listen, and so on. Today we don't really stick not behind any random verb. Instead, its use has been largely limited to a position after the initial word in a verb phrase. But what about am not? As thin i am not, we don't have amet, but there was once a contraction for that phrase which evolved around the same time as all those other contractions. All these contractions were in place by the 16 hundreds, by the time of shakespeare. Notice that this is