My husbands family are the Cossars around here, in NH. I was rather surprised to see Cossars in MD and other places as the name is uncomman around here. Actually I was told that the name is a shortend version of Cossarboom/baum, I'm not really sure if that is the correct spelling (I'm pretty sure its not) Do you know what nationality the name is? My husband older relatives came here from Maine but it is thought that they came from Canada? For some strange reason nobody seems to know!! Well It was nice to find some more Cossars. Thanks for any feedback.