On April 3 and 4, 1917, German U-boats sunk the Paraná, a Brazilian ship, and the Monte Protegido, an Argentinean vessel. The two countries’ populations demonstrated in indignation. More ships were sunk, and on this day, Brazil declared war against the Triple Alliance. Argentina reaffirmed its neutrality. The Brazilian war effort was largely symbolic, with a few ships participating in the Battle of the Atlantic and 23,500 soldiers fighting on the Western Front, but it changed the direction of Brazilian history. Debate over the conflict in the public arena led the country, strongly Francophile and pro-Ally, to reconsider its relationship with a Europe that was mired in barbarity. With the decline of the founding European model, new political identities would emerge and eventually take hold of the whole continent.