Final answer:
The ultimate cause of the Cholera outbreak in Golden Square, London was contaminated water in the Broad Street Pump, specifically sewage. Dr. John Snow's studies and interventions greatly reduced the number of deaths during the epidemic and revolutionized understanding of disease transmission.
Step-by-step explanation:
The ultimate cause of the Cholera outbreak in Golden Square, London was contaminated water in the Broad Street Pump. The source of that contamination was later found to be sewage. Dr. John Snow, a British physician, conducted studies and mapped the number of deaths around water sources, identifying the Broad Street pump as the main culprit. He worked with other officials to remove the handle of the pump, which greatly reduced the number of deaths during the epidemic. Snow's work revolutionized our understanding of disease transmission and led to significant improvements in public health.