Which sentence states a fact?

 - African American explorer Matthew Henson was the bravest explorer of the 1909 North Pole expedition.
 - In 1909, African American explorer Matthew Henson became one of the first people to reach the North Pole.
The second sentence states a fact. It can be verified by researching the life of Matthew Henson.
In 1909, African American explorer Matthew Henson became one of the first people to reach the North Pole.
The first sentence states an opinion. Bravest indicates a personal judgment.
African American explorer Matthew Henson was the bravest explorer of the 1909 North Pole expedition.