The prevalent theory is that most, if not all dogs evolved from wolves.
Around 100,000 years ago, it is theorized, the humans of that age developed a social structure.
The men would hunt in groups, and bring their kill back where their women and children were.
Wolves would come to the fringes of these areas and eat anything left of the kill that they could get to.
Probably some of them, especially abandoned or orphaned pups, would be brought into the enclave and raised and trained to help in the work required for survival.
Although there is no evidence that dog collars or leashes used during this era, it could reasonably assumed that some sort of restraint was used to keep the dogs from leaving.
There have been bones of dogs found by archeologists which are more than 8000 years old.
The oldest dog in recorded history is the Pharaoh Hound.
It is depicted on an ancient Egyptian disc which is estimated to be about 4000 years old.
However, some research indicates that the Pharaoh Hound was originally bred in Malta where it was used to hunt rabbits and was brought to Egypt by the Phoenician tradesmen about 3000 BCE.
The Egyptians used it for hunting gazelle.
Again it would be reasonable to assume that dog collars and leashes would be used as part of the training equipment although no mention of there use is in the literature.
A good example of dogs raised to help in survival is the Canadian Eskimo dog, which migrated with the Intuit people from about 1100 to1200 AD.
The dogs provided transportation by pulling sleds, helped in the hunt by finding seal breathing holes in the ice, and protected their masters by warding off polar bears.
Without their dogs, the Intuit people would not have survived in the harsh arctic conditions.
As they became more and more domesticated, dogs were selectively bred for different tasks that their owners/masters needed.
Some were bred down in size so they could be held in ones lap and became fashion statements for royalty.
The selective breeding, including inbreeding, continues to this day.
There are presently more than 800 different breeds, although not all are recognized by the American Kennel Club.
With the latest designer dog craze, new "breeds" are being generated by intentionally cross breeding dogs of different breeds.
Throughout the evolution of all the different breeds, some of the wolf characteristics are still evident.
The most significant ones are dominant and submissive behavior.
The first laws regarding dogs were enacted during the reign of the Pharos of Egypt.
The first known recorded dog licensing was in Germany in 1598.
In 1797, Amsterdam Holland was taxing dogs and issuing dog collars and most of Europe was issuing dog collars and licensing dogs in the 1800's.
The first anti cruelty laws were enacted in New York City in 1856.
There is no record of the first use of dog collars.
Leeds Castle, located in Maidstone, Kent, England has a museum of dog collars that has collars that date back to the 1500's.
Most of their collars are from Europe with some of the most ornate ones coming from Austria and Germany that were made in the 17th and 18th centuries.