Only one year later, the Swiss government invited the governments of all European countries, as well as the United States, Brazil, and Mexico, to attend an official diplomatic conference. Sixteen countries sent a total of twenty-six delegates to Geneva. The meeting was presided over by General Guillaume Henri Dufour. Signed at the Alhambra room at Geneva's Hotel de Ville (city hall) on 22 August 1864, the conference adopted the first Geneva Convention "for the Amelioration of the Condition of the Wounded in Armies in the Field". Representatives of 12 states signed the convention: