This is a simple guide to the development of the modern horse. It is a basic history to avoid controversy as there are conflicting opinions.
It was likely that it was during the Pleistocene era Around 3 million years ago. the first recognizable horse ancestor had arrived. This was the generic ancestor of all horse types from he Ass to the Zebra. The horse existed for many years alongside prehistoric man and ever since the history of man and the horse is one of mutual collaboration. No one knows when the horse first attracted mans attention as a food item, but as the relationship developed it became clear this animal could be more useful if it could be tamed. It man discovered that a young horse is easy to train if if training is started when it can leave its mother.

The horse's first task was probably as a pack animal, at this time man was still a nomadic hunter and horses may have been invaluable on the yearly migration to the summer hunting grounds, and in the autumn south to the winter quarters.

As agriculture developed it spread through Europe and Asia, and man discovered the larger breeds of horse could plough alongside the oxen.

The big breakthrough was when man discovered using inter breeding methods he could breed larger and stronger horses. It was at this stage, that they found they could replace the pack horses burden and ride the horse.

The development of Riding was a big deal, trade expanded and man could travel further and colonize uninhabited areas. But trade also demanded pack horses and the trend to bread larger and stronger horses began in earnest.

As there are today horses would have existed in a variety of sizes, and as they were of the same genus breeding and development of horse types was possible. Breeding from the largest available animals would over time produce bigger and more useful animals.

Did man create the horse and did the horse create civilization

Although this development would take some time, late prehistoric man was intelligent enough to undertake the systematic development of riding and light load pack horses. *During this period the wheel was invented and carts and wagons started to develop*, trade routes expanded and Kingdoms and Empires were founded.

The development of a more organized society and the ending of the nomadic life called for a further development in use mans best friend.
Owing to the development of basic roads pack horsed the first wheeled vehicles appeared and with that development, this would have exposed the fact the basic horse of the time was too small, no bigger then what we now call a pony. This state of affairs can be confirmed by the stages in the development of the chariot.

Early chariots were propelled by 4 or occasionally 6 horses, this is a testament to the lack of horsepower that individual horses could supply. The Celts providing a good example of the flowering of the early chariot as a war machine. As horses became larger and stronger the number used in chariots reduced.

The big breakthrough came with the arrival of the early empires in China, Africa Greece and Rome who independently developed mounted armies. Horses were simply selectively bread and slowly became bigger and stronger. As stronger horses became available the armies started to quickly developed cavalry. The bigger and stronger riding horses were also used to establish the first basic messenger systems postal networks the foundation of the postal system.

The chariot would gradually fall out of favor when horses could carry a rider. It was a remarkably long time until the stirrup was developed, the Romans had still had not fully developed them at the time of the conquest of Britain. The Chinese of the Jin Dynasty are generally credited with the invention of the stirrup around 100 AD. The proof being pottery figures of mounted horsemen using stirrups. The cavalry horse appeared and took its place in world history. The riding horse had finally became established.

Although there were still many pack and draught horses they were not much larger than the riding horses of the period. The need for a heavier more powerful horse was becoming apparent, agriculture and trade horse needed more horsepower. And all this before the fall of Troy.

*

Army's were destined to evolve and breed suitable cavalry horses until the 19th-century when it became obvious that the horse had no place on the modern battlefield.