Why did Ramesses II have red hair?

Excuse me, could you elaborate on the statement that Ramesses II, the renowned Pharaoh of Egypt, possessed red hair? Is there any historical evidence or archaeological findings that support this claim? Could it be a misconception or a cultural interpretation that has been passed down through generations? And if indeed he did have red hair, what might be the reasons behind this unique physical trait in an individual from that era and region?