The 1859 Carrington event is the most intense geomagnetic storm in recorded history, and it was observed to affect the magnetic field measured on Earth. The literature provides numerous explanations for the observed perturbation in the magnetic field, with debate on what dominated the event. Our analysis shows a combination of causes of similar sizes. Previous analyses generally rely upon the observed magnetic field perturbation at Colaba, India; historic newspaper reports; and empirical models. We expand the analysis using two Space Weather Modeling Framework simulations to examine what drove the event. We compute contributions from various currents and regions around the Earth. We find that a combination of currents and regions significantly contribute to the magnetic field on the Earth's surface. The specifics change as the storm evolves.