Aglondir was born and grew up in the Morthond Vale, known in Westron as Blackroot, in the west of Lamedon. Like many of those living in the shadow of the White Mountains, his family were members of a close-knit farming community, and as such Aglondir did not see very much of outsiders, nor the outside world. This all changed when the family farm was devastated by harsh seasons, and Aglondir had to move to the city of Calembel to find work at the tender age of fifteen.

In Calembel, Aglondir worked as a stable boy, mucking out and feeding the horses for soldiers and travellers. It was menial labour and, as fond as he was of the stable-master, Aglondir desired to see more of the world. As a result, he joined the Gondorian army at the age of nineteen. Due to his skill with a bow, as well as his countryside background, Aglondir was quickly drafted into Gondor's ranger battalions.

Aglondir spent the next twelve years as a ranger in Gondor's army. He spent much of his time in the forests of Ithilien, ambushing orcish raiders or evil men from the south. However, he also spent much of his time fighting in themultiple defenses and offensives of Osgiliath. During his time as a ranger, Aglondir grew very fond of his fellow rangers as well as the wilderness he had come to call home.

All of this was to change, however, when his company spent an evening camped in the lands of a young noble. The noble started shouting orders at some of his fellow rangers, as well as Aglondir himself. When Aglondir talked back, the noble threatened to have him hanged, but Aglondir persisted, coming to eventually breaking the noble's nose. Aglondir was then to be executed on the spot, and it was all Aglondir's commander could do to offer him exile over death.

Now no longer welcome in the lands he used to call home, Aglondir travelled far to the west. To avoid prosecution, Aglondir couldn't travel through Gondor to visit his home. Instead, he travelled along the Entwash and into Rohan, travelling to the north of the white mountains. He travelled on through the gap of Rohan, passing by Edoras. Here he joined the North-South road and travelled north, aiming to reach Breeland through Andrath. However, in the marshes near Tharbad, he was beset upon by an orcish raiding party. He managed to fell three of his attackers before a poisoned arrow struck him in the right shoulder. Quickly falling unconscious, Aglondir feared he had travelled all this way just to die in a swamp.

However, Aglondir awoke in Imladris. It turned out that a group of elves had been tracking the orcs and managed to catch them as they fell upon Aglondir. With the help of elvish medicine, Aglondir quickly recovered, but he remained in Imladris for a while. It was here among the elves that he leaved to speak westron. Also, while he had learned the rudiments of medicine as a ranger, the elves taught him a great deal about their healing arts. 

Aglondir finally left the refuge of the elves after nearly two years amongst their company. It was from there that he travelled east, finally reaching his destination, Bree, where the lords of Gondor held no power. Here, he hopes to rebuild his life. However, he is ever fearful that his past might one day catch up with him, so he keeps a keen eye out for any noble of Gondor looking to carry about the sentence he was given years ago.