Of all the mammals in the world, the wolf had range greater then any other (save the human). Sadly, this is no longer true. They have been driven out of most of their natural homes, and can now only been found in small numbers in small portions of the world. All wolves in the UK were wiped out by the 18th century, and the red wolf has only recently been re-introduced into the wild.
Different subspecies of wolves can be found in almost any kind of habitat. Species like the Arabian wolf can be found in deserts, while Arctic wolves inhabit far colder habitats.