The Gondorian Empire was founded by King Eldamil in FA 219, after the Great Knight of Dol Amroth Purge. He then declared war on his neighbours and began a war of conquest that would later be continued by his son and grandson, Elessar II and Elessar III.
After the Great Knight of Dol Amroth Purge, the king of Gondor, Eldamil, declared war on the kingdom of Harad. The new king of the Haradrim, Fahleen, hastily built up his army and marched into Gondorian territory. Eldamil hastily gathered his forces and petitioned Rohan for aid. The requested help was sent and at the Battle of Emyn Arnen, the army of Harad was driven back.
Eldamil pushed his advantage and invaded Harad, prompting Prince Morzan to send a request to the Easterlings of Rhun for reinforcements. The king of the Easterlings, Nidalas, sent a small force of pikemen and cavalry to Harad, planning to attack Gondor and draw Eladmil's forces out of Harad. Then Fahleen could use his army to attack Gondor from the south, thereby trapping the realm between two foes. However, all did not go according to plan.