Extinct Big Dog Breeds: You Won’t Believe These Ancient Giants Once Walked The Earth

The Moscow Water Dog, known by several names like Moscow Diver and Moscow Retriever, was a rare breed born from the lineage of the Newfoundland, Caucasian Shepherd Dog, and East European Shepherd. 

Sadly, this remarkable giant dog breed is now extinct, but its legacy lives on through the development of the Black Russian Terrier.[Citation Needed]

Uniquely, the Moscow Water Dog was exclusively bred by the Red Star Kennels, a state-operated institution with a mission to provide diligent working dogs for the armed forces of the Soviet Union. 

However, the breeding program took an unexpected turn when these dogs, instead of rescuing drowning victims, would, on occasion, act aggressively toward them, leading to the discontinuation of the program.

Though precise physical descriptions of the Moscow Water Dog are limited, we can make an educated guess about its size. This substantial canine likely fell in the range of 110 to 140 pounds, making it quite the heavyweight. When fully grown, this dog probably stood tall at about 26 to 30 inches, drawing from the typical heights of its parent breeds.

The Alpine Mastiff, also known as the Saint Bernard, is a large and imposing breed. Typically, an adult Saint Bernard can weigh anywhere from 140 to 180 pounds (63 to 82 kilograms) or even more in some cases. 

Their height at the shoulder usually ranges from 26 to 30 inches (66 to 76 centimeters). These majestic dogs are known for their impressive size and strength, which makes them excellent working dogs in alpine rescues.

The Alpine Mastiff, with a history dating back to before 500 B.C. in northern Europe, made its first documented appearance in 1829. A colossal light brindle dog named 'L'Ami' was brought to England from the Great St. Bernard convent and exhibited in London and Liverpool, proudly claiming the title of the largest dog of its time.

However, the Alpine Mastiff's story took a tragic turn, leading to its extinction in 1815. Excessive crossbreeding with other large mountain dogs in Europe played a pivotal role in this demise. 

In the pursuit of creating numerous giant descendants, these dogs were subjected to extensive crossbreeding, gradually diminishing their numbers due to the absence of conservation efforts.

The Bullenbeisser was a robust and powerful breed known for its substantial size. These dogs typically weighed between 75 to 110 pounds (34 to 50 kilograms). 

They stood at a shoulder height of about 23 to 27 inches (58 to 68 centimeters). The Bullenbeisser's impressive size made them well-suited for their historical roles as hunting and working dogs, known for their strength and agility.

The Bullenbeisser, or German Bulldog, was a robust and agile breed closely associated with the Bärenbeisser and Boxer. It had two regional varieties, the Brabanter Bullenbeisser and Danziger Bullenbeisser. 

Rather than experiencing a decline in its qualities, the Bullenbeisser faced extinction due to extensive crossbreeding. In the late 1870s, German breeders Roberth, Konig, and Hopner used this breed to create the Boxer. 

By 1900, around 30 Bullenbeissers were already crossed with Bulldogs from the British Isles. Initially, this created a 50/50 blood composition, but later, German breeders introduced various Bulldogs and Boxers, leading to a breed unrecognizable after World War II. 

The incorporation of substantial German blood into the Boxer breed aimed to reduce excessive white coloration and meet the demand for a popular breed. Today's Boxer carries some of the Bullenbeisser's strength and character.

This was one of the largest dog breeds ever. The size of Molossus dogs can vary, as the term "Molossus" refers to a group of breeds rather than a specific breed. Molossus dogs are typically large and muscular, characterized by their strong build. 

They can range from 70 to 200 pounds (32 to 91 kilograms) or more in weight. Their height at the shoulder varies between 18 to 36 inches (46 to 91 centimeters) or more, depending on the specific breed within the Molossus group. 

Some well-known Molossus breeds include the Mastiff, Bulldog, and Saint Bernard, all of which exhibit the distinctive traits of the Molossus group, such as their imposing size and robust appearance. These dogs were historically bred for various purposes, including guarding, herding, and working and companion animals.

The Dogo Cubano, also known as the Cuban Mastiff, was a substantial and powerful breed. These dogs were typically large, with males weighing between 100 to 160 pounds (45 to 73 kilograms) and females ranging from 80 to 130 pounds (36 to 59 kilograms). 

In terms of height, they stood around 20 to 24 inches (51 to 61 centimeters) at the shoulder. The Dogo Cubano was known for its muscular and imposing build, making it an effective guard and hunting dog in its native Cuba. 

Regrettably, their historical purpose was far from noble, as they were specifically bred for tracking and hunting down escaped slaves.

Following the abolition of slavery, the demand for these dogs declined, eventually leading to their extinction. However, it's believed that their legacy lives on through the influence on several modern breeds, including the Dogo Argentino and American Pit Bull Terrier. 

Despite their troubling history, the Dogo Cubano's genetic contributions continue in the descendants who have taken on new roles as loyal and beloved companions.

The Argentine Polar Dog, a massive breed weighing 130 pounds, was carefully bred to assist the Argentinian army in their expeditions across Antarctica. These dogs were a unique blend of cold-weather breeds, including Huskies, Malamutes, Manchurian Spitzes, and Greenland Dogs.

Remarkably, these dogs only became extinct quite recently, in 1994 to be precise. Their years of isolation in Antarctica, where they had no contact with other dogs, left them vulnerable to common canine diseases. 

Unfortunately, upon their return to South America, these diseases took a devastating toll, ultimately leading to their extinction.

So there you have it, the giant dogs that went extinct. It’s sad that they went extinct mostly due to we humans, but they are still present in their descendants and continue to serve as a stark reminder that conversation is always needed, even for dogs.