Founder Ymir

"'I hope that one day you'll be able to see how beautiful this world truly is.' - Rose Quartz to her unborn daughter"Founder Ymir (or Ymir Fritz) was the first person to gain the power of the Titans. She is the daughter of Rose Quartz. Ymir was a slave of the Eldian King, who abused her power to bring prosperity to his kingdom and devastating the neighboring kingdom of Marley, as well as the rest of the world. Thirteen years after gaining Titan powers she was killed while thwarting an attempt by Pearl to assassinate the king. Following her death, Ymir's daughters, Maria, Rose and Sheena, were forced to consume her corpse.

Personality
Ymir was portrayed in Eldian folklore and mythology as a kind and compassionate young girl who was always thinking of others, much like her mother. In reality, however, she was a slave with no will of her own. As a human-gem hybrid, the powers of her mother's gemstone were connected to her emotions and motivations; since she knew nothing except to be unquestionably obedient to those above her (as well as how she believed that she could be nothing more than a slave), the gemstone was nothing more than a decoration.

She was wholly submissive to the Eldian King, obeying his every command and even sacrificing herself for him. Even in death she remained blindly obedient to the royal family. It would not be until 2000 years after her death that she would finally embrace her own free will, thanks to Eren Jaeger.

History
At some point after the end of the Rebellion, Rose Quartz fell in love with an unknown man from a village on the outskirts of Eldia. Although she told her close comrades, Pearl and Bloodstone, that she planned to give up her physical body in order to have a child, she did not tell them where the village in question was, in fear of leading the King straight to the village. Unfortunately, the villagers ended up captured by the Eldians anyway several years later, and had their tongues cut out. At one point, the King accused the slaves of allowing a pig to escape, threatening violence if they did not (figuratively) speak up. Frightened by the prospect of further brutal torture, the slaves were quick to give up Ymir, who immediately accepted the accusation. The King released her, only to send his soldiers after her to hunt her down for sport. The wounded and desperate Ymir sought shelter in a cave at the base of a tree, where she ended up falling into a pit and came into contact with a huge Gem Cluster, resulting in the birth of the first Founding Titan.

Having finally found Rose Quartz' daughter, Bloodstone and Pearl were eager to become Ymir's caretakers, which the king agreed to. The king used Ymir's powers to further expand Eldia's power, wealth and prosperity, destroying its enemy Marley in the process. As a reward for her "service," King Fritz made Ymir his concubine; together they had three daughters, Maria, Rose and Sheena.

Both Bloodstone and Pearl failed to develop any sort of emotional bond with Ymir, who merely saw them as authority figures to obey (although they developed such a bond with each of her three daughters). Pearl attempted to reveal Ymir's true identity to her, but it ended up falling on deaf ears. 13 years after Ymir gained her Titan powers, Pearl attempted to assassinate the King, but ended up killing Ymir instead. Pearl ended up getting shattered, leaving Bloodstone as the only Crystal Gem left on Earth. Upon death, Ymir found herself in a mysterious, barren land, where she would reside for the next 2,000 years.

Desperate to retain Ymir's powers, the king forced his daughters to cannibalize their mother's corpse. As Ymir's bloodline grew, her soul was divided into Nine Titans.