((This is a short history, and knowledge of the mentioned events can be found through the chatter of the old of Bree, the Bree Archive room, or from Elaese herself. It is brief, because she likes to keep her business her own.))
Elaese was born Elizabeth Quincy, daughter of Merie Blythe and her husband Danor Quincy, a child concieved out of marriage. Although the two married shortly after conception, the Blythe family revoked all ties to their daughter and refused to recognize the child. Nonetheless, Merie and Danor married and moved to Brockan-a town now gone, far East of Bree and just North West of Rivendell. Elizabeth lived an idyllic farmtown life, her father took to raising sheep and her uncles lived with them-keeping crops.

When Elizabeth reached five, Brockan was destroyed by maurading goblins. Elizabeth and her mother escaped to the river briefly, but were overtaken by reinforcements arriving from the west. Taking her daughter to the docks, Merie placed Elizabeth into a boat and pushed her down river until a bolt took the use of her leg. She pushed Elizabeth into the deep current and fell into the water herself, drowning. Elizabeth rode the boat to and over the falls above Imladris(Rivendell), the boat being destroyed on impact. She was knocked unconscious and floated to the riverbanks of a private garden whence she was discovered by Amroth Cúthalion, a young elven lord of 125 years. 

Many years before, Amroth had recieved a vision that predicted his path would arrive at The Fall, and he mistook it for a war or failing of a peoples. Seeing Elizabeth's arrival via The Falls, however, he recanted his vigilance for war and percieved her as his new responsibility. Upon contacting the Blythe family(as the Quincy family was destroyed in it's completion at Brockan), Amroth discovered the events surrounding her birth and the Blythe family staunchly refused to recognise her as alive. They legally revoked her right of succession and 'buried' her with her parents in the Bree cemetary. She lost her name and any title of succession, and Amroth took her as his child-renaming her Elaese in honour of her mother's nickname for her.

Elaese was thus raised in Imladris for the duration of her childhood-except for when Amroth was sent on patrol in her later years-whence she traveled with him. She learned the arts of combat, healing, and marksmanship from him and excelled in all. At age 22, she set out to make a name for herself amongst her own people. She settled abouts Bree-land, patroling the highways and ousting a bandit lord in the next two years.

She is known about Breeland as Eli now, and her name is synonymous with vengeance. When a tough job needs to be done, many come to her. The price isn't always low, but the job is always well-done.