“Rapunzel, before I met your father, I was so much like you. I had no idea what I was supposed to do in this world. So I went out and found my own way.”
―Arianna to Rapunzel.
Arianna is the Queen of the kingdom Corona. In Tangled: Before Ever After, Arianna tells Rapunzel that, at a young age, she was very much like her daughter in that she felt lost in the world and longed to find her calling. During this time, she lived her life as an adventurer, exploring remote continents, besting violent storms and helping local villagers restore their worn homes. At some point, she would meet Frederic, marry him, and assume the role of queen. According to Flynn Rider's narration in the original Tangled, Arianna is a beloved monarch who rules the kingdom with grace and wisdom.
In Tangled, Arianna is shown to love her daughter and her husband dearly: when Rapunzel is born, she smiles adoringly, cuddling and picking her up. She then silently comforts her husband on the day of the lantern festival, gently touching his face when he cries. These scenes show that she is caring, supportive, and kindly. She is also shown to be very accepting, immediately welcoming Eugene into the royal family upon realizing he was partially responsible for her daughter's return.
Arianna's personality is slightly expanded in Tangled: Before Ever After, where her loving and supportive nature is emphasized by her way of raising Rapunzel — especially compared to her husband. Unlike the paranoid Frederic who fears for Rapunzel's safety nearly every waking moment, Arianna simply relishes in having a complete family once more. She also sympathizes with Rapunzel's longing to learn more about the world, and herself, and encourages her to do just that. Gentle and soft-spoken, Arianna quickly established herself as someone Rapunzel can confide in during times of uncertainty.
In regards to Rapunzel and Frederic's somewhat strained relationship, Arianna advices Frederic to lower his defenses and trust that their daughter will prevail as a wise ruler when her time comes. She openly believes the idea that teenagers are a rather complex age-group that requires patience and understanding from the parent to properly raise, explaining her methods of raising Rapunzel.
It's shown later on that she and Rapunzel have developed a deep mother-daughter bond. Arianna gave motherly wisdom about how Rapunzel should best portray herself in her royal portrait. When Rapunzel decided how she wanted her royal portrait, she made it of her with her mother.
Arianna bears a striking resemblance to her daughter; near identical, bright green eyes, with similar facial features. She, along with Frederic, also share Rapunzel's brown hair (after it was cut). Arianna's hair almost reaches her waist. It is parted in the same way as Rapunzel's is, and the upper layer is tied back neatly in a sort of updo.
Arianna is more involved in the movie, even though she does not have a speaking role like her spouse, Frederic. She contracted an unknown illness while heavily pregnant with Rapunzel, and she was going to die, along with her child, from the illness. The guards, however, found the magical golden flower that, through a traditional medicinal method such as extracting a plant's essence by boiling it in water, fully healed her, which also successfully helped with the birth of Rapunzel. Not long afterward, Mother Gothel snuck into the castle to kidnap Rapunzel, who held the powers she believed were rightfully hers. As a loving mother, Arianna along with the King, was devastated to have her baby taken away. Eighteen years later, she and the King continued to hold the lantern festival to call their daughter home and were just as emotionally shaken as the day she disappeared. Arianna did not return to the scene until a guard came to report Rapunzel's return. Although she was not able to immediately recognize and embrace Rapunzel as her long lost daughter upon first sight, Arianna's maternal instinct and striking resemblance to Rapunzel brought the family together immediately. As she, her husband and Rapunzel sank to the ground in a powerful embrace, Arianna silently extended her hand to Eugene in speechless gratitude. As he took it, she pulled him in to join them. She was last seen smiling and hugging Rapunzel and Frederic towards the end of the movie.
Arianna has a brief appearance in Tangled Ever After. In Maximus' dream sequence after he loses the rings, Arianna exclaims from the audience that the rings were her grandmother's. She also appears at the end, alongside Frederic, giving Maximus and Pascal a surprised look that they were both dirty and messy, and also smiling happily as her daughter is married.