Sienna Khan

"I was one of the first to suggest violence where violence was necessary. Peace bred complacency and acceptance of our place in the world. I will not allow humanity to push us down without pushing them back"

- Leading into explaining to Adam how he took her policy too far.

Sienna Khan is a minor antagonist introduced in Volume 5 of RWBY. She was the leader of the White Fang, before Adam Taurus killed her in a coup he engineered.

She was voiced by Monica Jean Rial.

Background
Sienna became leader of the White Fang after Ghira stepped down as leader of the organization. Adam Tauru meets for an assault on Haven Academy and Hazel expresses frustratioon.

She is seen with a green waist cincher with red rims that has a black belt over it, which fastens a green pouch on her right hip. Aside from green sandals that have a black elbow length fingerless glove on her right hand.

Trivia

 * "Sienna" refers to a reddish shade of brown, while Khan translates as "sovereign," "king", or "military leader", in a number of languages.
 * She may allude to Shere Khan from Rudyard Kipling's The Jungle Book, which is all the more evident as the predecessor, Ghira Belladonna, the previous leader of the White Fang, may allude to Bagheera from the same story.
 * Shere Khan is a tiger, and Sienna is a tiger Faunus indicated by her ears.
 * Incidentally, Shere Khan in the original tale was stampeded by bulls, while Sienna Khan was assassinated by Adam Taurus, who alludes to a bull.

source

 * Sienna Khan on the RWBY Wiki