What is the difference between a German Rottweiler and an American Rottweiler?
German Rottweiler is TYPICALLY a term Backyard Breeders use to make their Rottweiler seem more special. Usually they call it a German "Block head" Rottweiler or something along those lines
Here is a great article about the difference between American/German Rottweilers
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German Rottweiler or American Rottweiler
If you own a Rottweiler you’ve probably been asked (on more than one occasion), "Is your Rottweiler a German Rottweiler or American Rottweiler?" When I was first asked the question I was a bit baffled because I thought that there was only one kind of Rottweiler. Then the all knowing individual I was speaking to proceeded to explain to me that German Rotties were shorter, stockier and have a bigger blockier head, and American Rotties were taller and leggier without as blocky a head. (Of course, there are several variations to this mythology – American Rotties have bigger ears, German Rotties have bigger teeth, you name it someone’s probably said it.)
Wow! I thought I’d really learned something that day. Well, I guessed Jericho must be a German Rottie because he had a really blocky head, and Sherman must be an American Rottweiler because he has pretty long legs. Now after hanging out in the Rottweiler community and discussing this issue with some friends who have been in Rotties for 20 years, it turns out my first impression was right. There aren’t any distinctive types of Rottweilers, and only one factor determines whether a Rottweiler is ‘American’ or ‘German’ – their place of birth. Rottweilers born in America are American Rottweilers just as people born in America are called Americans. Dogs born in Germany are German Rottweilers. Earth shattering, mind boggling stuff, huh? How can that be, you ask?
Here’s how. The breed standard that the American Kennel Club (AKC) has established for Rottweilers is extremely similar (almost identical) to that of the Allgemeiner Deutscher Rottweiler-Klub (ADRK aka the Rottweiler Club of Germany). The only inconsistency between the two standards is the height allowance. The AKC’s standard is a few centimeters different than that set by the ADRK.
The major difference between dogs bred in the US and those produced in Germany results from the fact that the ADRK is very selective about which dogs are *allowed* to reproduce, i.e. dogs have to pass certain physical and temperamental requirements before the owners can breed them. Although ethical American breeders follow similar guidelines, the vast majority of people who breed Rottweilers are high risk breeders who are either ignorant of the fact that a breed standard exists or simply do not care whether or not their dog falls within the standard. The indiscriminant breeding by these Americans produces Rottweilers who do not conform to the standard and who are highly inferior to those bred by American Code of Ethics breeders and especially German ADRK members.
While ethical breeders from each country probably have certain traits or aspects of their dogs that they prefer to enhance through breeding, the similarity of the breed standards for each country keeps these breeders in check and demands that they breed dogs who are within the standards established for the breed. If one were to take a Rottweiler born to an American Code of Ethics breeder and put it side by side with a Rottweiler born in Germany to an ADRK breeder, most people would be unable to tell which dog was born in Germany and which dog was born in America. Unless, of course, the dogs were facing away from the observer, then one could quickly determine which dog was born in Germany because tail docking is now banned in most European countries.
In summation while there are individuals in several countries who breed Rottweilers there is still only one breed or type of Rottweiler and that dog is called a Rottweiler. So the next time you take your Rottweiler for a walk around the block, and someone asks you if your dog is American or German, you can reply with confidence that your dog is ________ (fill in country of birth) because your dog was born in _________, or you can really throw ‘em for a loop like I do when I tell them my dog is a Texas Rottweiler. 
