Wasn’t on my radar, I have to say. The Nobel Committee’s announcement is here; the OPCW statement is on their front page. I was going to point out that the Nobel committee has previously recognized efforts to control weapons, but they beat me to it:

Disarmament figures prominently in Alfred Nobel’s will. The Norwegian Nobel Committee has through numerous prizes underlined the need to do away with nuclear weapons. By means of the present award to the OPCW, the Committee is seeking to contribute to the elimination of chemical weapons.

Here’s the full text of Nobel’s will. The relevant part reads:

The whole of my remaining realizable estate shall be dealt with in the following way: the capital, invested in safe securities by my executors, shall constitute a fund, the interest on which shall be annually distributed in the form of prizes to those who, during the preceding year, shall have conferred the greatest benefit to mankind. The said interest shall be divided into five equal parts…one part to the person who shall have done the most or the best work for fraternity between nations, for the abolition or reduction of standing armies and for the holding and promotion of peace congresses.