Hillary Karuza was born in Charlotte, North Carolina, USA. She began learning the cello at the age of four under the tutelage of Professor Janis Nilsen. After completing high school and studying art history in Florence, she enrolled in the cello program at the University of North Carolina under Professor Brent Wissick, where she graduated in 2002. That same year, she started her postgraduate studies at Pennsylvania State University in the class of Professor Kim Cook, where she earned her master's degree in 2004.

She has honed her skills in masterclasses with some of the greatest cellists of today, including Yo-Yo Ma, Lynn Harrell, Anner Bylsma, and Aldo Parisot. In 2004, she enrolled in a doctoral program at the University of North Carolina, Greensboro, in the class of Professor Brooks Whitehouse. However, after completing her first year, she moved to Croatia, where she was initially engaged as an external collaborator with the Opera Orchestra of the Croatian National Theatre in Split.

Hillary has been a permanent member of the Williamsport Symphony Orchestra and the Pennsylvania Chamber Orchestra and served as the assistant principal cellist of the Altoona Symphony Orchestra. Since 2002, she has been increasingly involved with baroque music, participating in the Penn State Baroque Ensemble, and in 2007, she co-founded the Omiš Baroque Ensemble.

She has performed as a soloist with the Split Chamber Orchestra and the Mostar Symphony Orchestra, as well as at major international festivals in Morges (Switzerland), Arezzo (Italy), and Salvador (Brazil).

Hillary has worked as a cello and double bass professor at the Lovro pl. Matačić Music School in Omiš, and since 2012, she has been teaching cello at the Josip Hatze Music School in Split. Since 2020, she has also been an external collaborator at the Academy of Arts in Split. Her students have won numerous awards at regional, national, and international competitions.