From The National WWII Museum (http://www.nww2m.com/2012/08/brazil-joins-up/):
“In 1942, Brazilian casualties numbered more than 1,000 at sea, all struck by German U-boats. Though the government under dictatorial President Getúlio Vargas sought neutrality—largely to avoid losing business with the powers on either side of the conflict—the people of Brazil largely commiserated with the Allied cause. On 22 August 1942, 79 years ago today, the nation of Brazil declared war on the Axis powers of Germany and Italy”.
https://www.rarenewspapers.com/view/624674
Here are some State Department telegrams regarding Brazil’s entry into the war:
740.0011 European War 1939/23852
The Brazilian Ambassador to the Secretary of State
No. 375/940.(00)
Washington, August 22, 1942.
Mr. Secretary of State:
Under instructions of my Government, and in accordance with the procedure adopted and the undertakings assumed in the Pan American Conferences of Buenos Aires and Lima, as well as in the meetings of Foreign Ministers, I have the honor to inform Your Excellency that, on the night; of the fifteenth to sixteenth of the present month, there were torpedoed, twenty miles off the coast of Sergipe, five Brazilian passenger vessels which were plying from one Brazilian port to another carrying, among others, pilgrims on their way to the São Paulo Eucharistic Congress.
One of the vessels, the Baependy, was carrying a troop contingent of one hundred twenty men who were not on the way to any war zone, having simply been transferred from one military region of the country to another.
Prior to this criminal act, with the loss of many lives, there had already been torpedoed by Axis submarines thirteen Brazilian vessels in international traffic.
At that time our attitude was one of simple protest against the violation, in these unnecessary and brutal acts, of the rules of law and of the principles of humanity which govern warfare on the high seas.
On this occasion, where the number of victims was of several hundreds, including women and children, the aggression was directed against our coastwise shipping and was carried into Brazilian waters against essentially peaceful navigation which, by its very nature, is devoid of any objective susceptible of favoring any belligerent nation, even American, or of injuring the interests of any third parties. They were passenger vessels and none was either operating in a war or blockade zone, or could be suspected of carrying cargoes for any of the adversaries of the Axis powers, since their ports of destination were exclusively Brazilian.
Their sinking off the Brazilian coasts is undisputably an act of direct aggression against Brazil and results in the extension of the war to South America.
By virtue of this fact, the Brazilian Government, through the Spanish Embassy and the Swiss Legation, has notified the governments of Germany and Italy that, in spite of its consistently pacific attitude, it is not possible to elude the fact that those countries have practiced against Brazil acts of war, creating a condition of belligerency which we are forced to recognize in the defense of our dignity, of our sovereignty, of our safety and of that of America, and to resist those acts to the extent of our strength.
I avail myself [etc.]
CARLOS MARTINS PEREIRA E SOUSA
740.0011 European War 1939/23741c: Telegram
The Secretary of State to the Chargé in Brazil
Washington, August 22, 1942.
2405.
The following telegrams have today been sent:
His Excellency Getulio Vargas, President of the United States of Brazil, Rio de Janeiro.
I have been informed that the United States of Brazil has today recognized that a state of war exists between Brazil on the one hand and Germany and Italy on the other hand.
On behalf of the Government and people of the United States I express to Your Excellency the profound emotion with which this courageous action has been received in this country. This solemn decision more firmly aligns the people of Brazil with the free peoples of the world in a relentless struggle against the lawless and predatory Axis powers. It adds power and strength, moral and material, to the armies of liberty. As brothers in arms, our soldiers and sailors will write a new page in the history of friendship, confidence, and cooperation which has marked since the earliest days of independence relations between your country and mine.
The action taken today by your Government has hastened the coming of the inevitable victory of freedom over oppression, of Christian religion over the forces of evil and darkness.
I send you my warmest personal regards and expressions of the fullest confidence in the success of our common cause.
FRANKLIN D. ROOSEVELT
His Excellency Oswaldo Aranha, Minister for Foreign Affairs, Rio de Janeiro.
I have received a note from the Brazilian Ambassador in Washington informing me that the Government of Brazil recognizes that a state of war exists between Brazil on the one hand and Germany and Italy on the other hand.
The people of the United States welcome the people of Brazil as brothers in arms and salute their high resolve and defiant courage in taking a position unequivocally at the side of the embattled freedom-loving nations of the world. Today a heavy blow has been dealt the Axis Powers, moral no less than military, when a great, peaceful and law-abiding nation is driven by unprovoked acts of ruthless barbarity to take up arms in self-defense. It comes as no surprise to my countrymen that the proud Brazilian Nation has chosen the risks and hardships of battle when confronted with wanton attacks on its sovereign dignity and rights.
The action of the Axis powers in attacking your great country and people is a further demonstration of the fact that those Powers will strike at any peace-loving nation as and when to do so will serve their purpose of world conquest, regardless of considerations of humanity and international law. It also brings into bold relief the basic principle upon which the solidarity of the American republics rests, namely, that an attack against any one of them is an attack against all of them. Each of the twenty-one American Republics are today equally in danger.
Together our two countries will face the future with serene confidence and high hearts.
I take pleasure in sending Your Excellency renewed assurances of my high personal esteem.
CORDELL HULL