The "beautiful yet slightly intimidating" Rowena Ravenclaw, one of the four Founders of Hogwarts School of Witchcraft and Wizardry.
Her great wisdom and skills can be seen from the fact that she was the one that designed the magical stairs in Hogwarts. The diadem is the only known possession left from Rowena, and it has inscribed "Wit beyond measure is man's greatest treasure" on it, which connects it to what Ravenclaw was mostly valued, wisdom. She was probably the most intelligent witch of her time.
Her House values sharp mind, wisdom, creativity, and cleverness in its members.
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