Förster produced numerous scientific works and promoted ethics, peace and international arbitration. He was aiming to improve the relations between France and Germany. Förster initiated the first international "race congress" in London in 1911.
Bourgeois was chairman of the French delegation to the Peace Conferences at The Hague 1899 and 1907. He was a member of the French parliament's peace group, and he was a proponent of international law and arbitration.