The novel "The Name of The Rose" by Umberto Eco achieved immense success due to a combination of several factors. These factors include its mystic elements, the incorporation of metaphysics and medieval history, and the unique blend of detective style and theology.

1. Mystic Elements:
The inclusion of mystic elements in the novel captivated readers and added an air of intrigue. The story is set in a monastery during the Middle Ages, where mysterious deaths occur. The presence of mysticism and the unknown creates an aura of suspense and engages the readers throughout the narrative.

2. Metaphysics and Medieval History:
"The Name of The Rose" delves into metaphysics and explores philosophical concepts such as semiotics, hermeneutics, and the nature of truth. The novel also provides a rich portrayal of the medieval period, depicting the social, cultural, and religious aspects of that time. This combination of metaphysical exploration and historical context appeals to readers interested in intellectual and historical subjects.

3. Detective Style:
The novel adopts a detective-style narrative, with the protagonist, William of Baskerville, tasked with solving a series of mysterious deaths in the abbey. This detective framework engages readers who enjoy suspenseful, investigative plots. The inclusion of clues, red herrings, and an unraveling of the truth keeps readers engaged and eager to uncover the secrets of the story.

4. Theology:
The novel intertwines theology with the detective plot, creating a unique and thought-provoking reading experience. It explores theological debates, religious conflicts, and the power struggles within the Church during the Middle Ages. The inclusion of theological themes adds depth and complexity to the storyline, appealing to readers interested in religious and philosophical discussions.

In conclusion, the huge success of "The Name of The Rose" can be attributed to the combination of its mystic elements, incorporation of metaphysics and medieval history, and the unique blend of detective style and theology. This multifaceted approach appeals to readers with diverse interests, creating a captivating and intellectually stimulating reading experience.