What does with an iron fist mean?

Could you please clarify what you mean by "with an iron fist"? This phrase is commonly used to describe a leader or ruler who governs or controls their subjects or territory in a strict, unyielding, and often oppressive manner. It implies a lack of flexibility, compassion, or negotiation in their decision-making processes. Is there a specific context or example you had in mind when you asked this question?