Here's why:
* Explicit References: Spenser himself makes it clear in the poem that Gloriana is meant to be Elizabeth. In Canto IX of Book III, the poet explicitly states that Gloriana's court is meant to mirror Elizabeth's court at Greenwich.
* Virtues and Character: Gloriana embodies many of the ideals associated with Elizabeth, such as her strength, wisdom, and her role as a powerful ruler. She is a symbol of England's glory and power, mirroring Elizabeth's reign as a golden age.
* Allegory of the Reign: *The Faerie Queene* can be seen as an allegory for Elizabeth's reign, with the various knights representing different aspects of her rule, and the battles and trials they face representing the challenges Elizabeth faced during her reign.
* Historical Context: The poem was written during Elizabeth's reign, and it was dedicated to her. Spenser was a loyal subject of the Queen, and it is likely that he intended the poem to be a tribute to her.
However, it's important to note that Gloriana is not simply a straightforward portrait of Elizabeth. She is also a complex and multifaceted character, representing ideals beyond the historical Queen. She embodies the virtues of chastity, justice, and mercy, reflecting the Elizabethan ideal of a virtuous and righteous ruler.
So, while Gloriana is undoubtedly a representation of Elizabeth I, she is also a much more complex and nuanced figure, embodying both the historical Queen and the ideal of a perfect ruler.