Born in Castel Gandolfo in the Papal States, near Rome, Pietro Savorgnan di Brazzà was the seventh son of Count Ascanio Savorgnan di Brazzà, a nobleman of Udine with many French connections, and his wife Giacinta Simonetti. Pietro was interested in exploration from an early age and won entry to the French naval school at Brest. He graduated as an ensign and sailed on the French ship Jeanne d'Arc to Algeria, where he took part in the crushing of Cheikh Mokrani's revolt.
Brazza first encountered Africa in 1872, while sailing on an anti-slavery mission near Gabon. His next ship was the Vénus, which stopped at Gabon regularly. In 1874 Brazza made two trips into the interior, up the Gabon and Ogooué rivers. He then proposed to the government that he explore the Ogooué to its source. With the help of friends in high places, including Jules Ferry and Leon Gambetta, he secured partial funding, the rest coming from his own pocket. He was granted French citizenship in 1874, and adopted the French spelling of his name. His efforts to gain citizenship had been aided by Louis Raymond de Montaignac de Chauvance, who acted as de Brazza's patron in the early years of his career.
In this expedition, which lasted from 1875–1878, 'armed' only with cotton textiles and tools to use for barter, and accompanied by Noel Ballay, a doctor, naturalist Alfred Marche, a sailor, thirteen Senegalese laptots and four local interpreters, Brazza charmed and talked his way deep inland. Upon his return to Paris he was fêted as a celebrity in the French press and was courted by the French political elite as the man to advance their imperialist ambitions in Africa. The French authorized a second mission, which was carried out 1879-1882. The French had adjudged his first mission a success and felt that a mission to the Congo Basin was needed to prevent Belgium from occupying the entire area. By following the Ogoué River upstream and proceeding overland to the Lefini River and then downstream, de Brazza succeeded in reaching the Congo River in 1880 without encroaching on Portuguese claims.
De Brazza then proposed to King Illoh Makoko of the Batekes that he place his kingdom under the protection of the French flag. Makoko, interested in trade possibilities and in gaining an edge over his rivals, signed the treaty. Makoko also arranged for the establishment of a French settlement at Mfoa on the Congo's Malebo Pool, a place later known as Brazzaville; after de Brazza's departure, the outpost was manned by two Laptots under the command of Senegalese Sergeant Malamine Camara, whose resourcefulness had impressed de Brazza during their several months togethet trekking inland from the coast. During this trip he encountered Stanley near Vivi. Brazza did not tell Stanley that he had just signed a treaty with Makoko; it took Stanley some months to realise that he had been beaten in the "race" set by his sponsor, King Léopold. Brazza was again celebrated in France for his efforts. The press dubbed him "le conquérant pacifique", the peaceful conqueror, for his success in ensuring French imperial expansion without waging war.
In 1883, De Brazza was named governor-general of the French Congo in 1886. He was dismissed in 1897 due to poor revenue from the colony and journalist reports of conditions for the natives that some said were "too good." For his part Brazza had become somewhat disillusioned with the exploitative and repressive practices of the concessionary companies, which he had witnessed first-hand.
De Brazza became a freemason in 1888. Initiated at the "Alsace-Lorraine" lodge in Paris, on June 26, 1888.
By 1905, stories had reached Paris of injustice, forced labour and brutality under the laissez-faire approach of the Congo's new governor, Emile Gentil, to the new concession companies set up by the French Colonial Office and condoned by Prosper Philippe Augouard, Catholic Bishop of the Congo. Brazza was sent to investigate these stories and the resulting report was revealing and damning, in spite of many obstructions placed in his path. When his deputy Félicien Challaye put the embarrassing report before the National Assembly, the report was suppressed.
The oppressive conditions in the French Congo continued for decades.
Brazza married Thérèse de Chambrun. As a result, Pierre de Chambrun and Charles de Chambrun were his brothers-in-law. Meanwhile, René de Chambrun, the son-in-law of Vichy France Prime Minister Pierre Laval, was his nephew.
The last tour of the Congo took a hard physical toll of Brazza, and on his return journey to Dakar he died of dysentery and fever (amid rumours that he had been poisoned). His body was repatriated to France and he was given a state funeral at Sainte-Clotilde, Paris, prior to interment at the cemetery of Père Lachaise. His widow, Thérèse, dissatisfied with the politicians' subsequent behaviour, had his body exhumed and reinterred in Algiers (capital of present-day Algeria). The epitaph for his burial site in Algiers reads: "une mémoire pure de sang humain" ("a memory untainted by human blood").
In February 2005 Presidents Nguesso of Congo, Ondimba of Gabon and Chirac of France gathered at a ceremony to lay the foundation stone for a memorial to Pierre de Brazza, a mausoleum of Italian marble. On 30 September 2006, de Brazza's remains were exhumed from Algiers along with those of his wife and four children. They were reinterred in Brazzaville on 3 October in the new marble mausoleum which had been prepared for them and had cost some 10 million dollars. The ceremony was attended by three African presidents and a French foreign minister, who paid tribute to his humanitarian work against slavery and the abuse of African workers.
The decision to honor Pierre de Brazza as a founding father of the Republic of the Congo has elicited protests among many Congolese. Mwinda Press, the journal of the Association of Congolese Democrats in France wrote articles quoting Théophile Obenga who depicted Pierre de Brazza as a colonizer and not a humanist, declaring him to have raped a Congolese woman, a princess and the equivalent of a Vestal Virgin, and to have pillaged villages, raising highly-charged questions as to why the colonizer should be revered as a national hero instead of the Congolese who fought against colonization.