In the 25th year of his majesty's reign, the Unicorn Empire's great explorer 'Coltombus' found the new continent of 'Equestria' and its inhabitants, a new race of pony, the Earth Ponies. A colony was established on the coast and named Manehatten in the 31st year of his majesty's reign. Then the Earth Ponies started to get hostile, no lives were taken until the 56th year of his majesty's reign, that's when the war started. The first war anyway.
Special thanks to 'TheEmpressEclipse', for proof reading.