The first thing I saw when I woke up this morning, from the BBC News: Former US President Jimmy Carter wins the Nobel Peace Prize for “decades of untiring effort to find peaceful solutions to international conflicts, to advance democracy and human rights, and to promote economic and social development.”
The Nobel site has a long history on the Nobel Peace Prize, including this bit on the first award to a US president:
"[Roosevelt] received the prize for his successful mediation to end the Russo-Japanese war and for his interest in arbitration, having provided the Hague arbitration court with its very first case. Internationally, however, he was best known for a rather bellicose posture, which certainly included the use of force. It is known that both the secretary and the relevant adviser of the Nobel Committee at that time were highly critical of an award to Roosevelt."
And the second, to Woodrow Wilson:
"In 1919, the Peace Prize was awarded to the President of the United States, Thomas Woodrow Wilson for his crucial role in establishing the League [of Nations]. Wilson had been nominated by many, including Venstre Prime Minister Gunnar Knudsen. In a certain sense the prize to Wilson was obvious; what still made it controversial, also among committee members, was that the League was part of the Versailles Treaty, which was regarded as diverging from the president's own ideal of 'peace without victory.'"