The International Woman Suffrage Alliance (IWSA) was founded by leading feminists in 1904. The organisation was devoted to securing women's suffrage and held regular international conferences. In 1915, it was due to take place in Berlin but was cancelled because of the war.
On a proposal by the Dutch feminist Dr. Aletta Jacobs, the International Women's Peace Congress was organised in The Hague as an alternative. The organising committee also included Belgian women. The organisation was not plain sailing, as many women found it difficult or even impossible to travel to The Hague; many were denied travel documents, and the British naval blockade made the Netherlands very difficult to reach. A ship with forty American women on board was held up, but eventually arrived in the Netherlands just in time for the opening of the conference.
The peace conference took place in The Hague Zoo. There were about 1000 attendees from the Netherlands and hundreds of foreign guests, representing a total of twelve countries. The five Belgian attendees had been granted special passes by the German occupant. Among the best-known participants were the American activist Jane Addams and the American author and pacifist Emily Greene Balch. Both were later to receive the Nobel Peace Prize for their efforts in the peace movement.
The conference had just one theme: peace. How could the war be brought to an end and how could countries go back to living in harmony with each other? A number of decisions were made concerning peace negotiations, mediation and non-violent conflict resolution, and the conference leaders were charged with the task of presenting these resolutions in person to the governments of warfaring and neutral countries. To this end, Aletta Jacobs and a few other women travelled to Germany, Austria, Italy, France, Great Britain and the United States. Another delegation went to Scandinavia and Russia.
 

'Internationale vrouwendag', De Vlaamsche Stem, 28 maart 1915, p. 4
Today, over 50 organisations worldwide are members of the IWSA's successor, the International Alliance of Women (IAW), which plays an important role in the United Nations, where it holds general consultative status.