First Easterling War

The First Easterling War was a series invasions, battles, and events that marked the beginning of Gondor's troubles with the Easterlings alone.

Background
The reason for the sudden attacks by the Easterlings at this time is not known. It was possibly due to the ancient hatred of the Men of the West going all the way back to the Edain, or toward the Númenóreans and the Dúnedain in general for many defeats they handed them over the centuries, most recently in the Last Alliance. The most likely answer was probably revenge or more likely greed and a desire to covet the lands of the Dúnedain. Gondor was in the midst of peace so they had the element of surprise.

Early stages
The war began in TA 490 when the Easterlings suddenly invaded Gondor. Not fully prepared for war, the Easterlings were successful and no doubt ravaged, pillaged, plundered, and caused much death in north-eastern Gondor particularly North Ithilien. As King Ostoher was growing old, he charged his son Tarostar with driving out the invaders. Gondor endured ten long years of their attacks until TA 500 when Tarostar, afterwards called Rómendacil I, the East-victor defeated them ending the long period violence.

Temporary Cessation of Hostilities
Tarostar's victory defeated the invaders but not utterly. The Easterlings continued to survive and recoup themselves in Rhûn while Rómendacil was busy with affairs of the realm. Forty-one years after their defeat, the Easterlings renewed their attacks on Gondor. Rómendacil once again led a host against them but was slain in battle that was probably lost by Gondor.

Finial Defeat of the Easterlings
The Easterling's new threat didn't last long. Rómendacil's son Turambar immediately became King of Gondor. Eager to avenge his father's death, Turambar assembled fresh armies and decisively defeated the Easterlings in a battle somewhere in the north-east of Gondor in TA 541.

End of War and Conquest of Rhûn
After his victory over the enemy, Turambar did not disband his armies and instead led them into Rhûn. After nine years of campaigning against the Easterlings, his armies finally conquered a large portion of Rhûn in TA 550. The conquered territory became the East-lands province of Gondor.

Legacy
The aftermath of the First Easterling War left the Easterlings defeated, non-threatening, and not able to make war on Gondor for over 1,300 years. It also laid the groundwork for the expansion of the realm of Gondor. The Northmen people of Rhovanion also became later allies of Gondor.