Brandt was the twelfth of 14 siblings. His father came from Hamburg, and traded in Finnmark before the family moved to Trondheim. Peter Andreas also started as a merchant trader in his home town. But he soon felt restless and the need to find something else in life. He married in 1814, and had six children. The youngest daughter, Wilhelmine, came to be a pioneer in genealogy in Norway. The family moved around in Norway before again settling in Trondheim around 1820. Brandt looked at business connections in the USA at an early stage, but nothing came of this.
Around 1830 the family moved to Christiania [now Oslo]. Here Brandt started newspaper activities. In 1832 he was the editor of Finmarkens og Nordlands Amtstidende, before the editorial staff moved to Tromsø the next year. Thereafter, in the tradition of Wergeland, he started to plan the publication of a Skilling-Magazin [a weekly paper] ("for the dissemination of generally useful knowledge"). This magazine came to have quite an influence and lasted until 1890. But even before the first issue was published, Brandt had left his family and his native country. The most reasonable explanation must have been financial trouble as he had acquired large debts.
He had possibly planned to join a brother-in-law who lived in Chile. Instead he ended up in Brazil. Random circumstances brought him into contact with the Danish natural historian Peter Wilhelm Lund, who was conducting archaeological studies in the south-east part of the country. In several limestone caves they made many prehistoric findings, such as bone remnants and cave paintings. These findings document earlier human life than anywhere else in South America. From 1836 to 1844 Brandt worked as an assistant for Lund. He assisted with surveying and registration, and displayed a formidable talent as a sketch artist. His precise drawings of findings and objects are admired even today. He also painted landscapes, people and animal life in a slightly naive'ish style. In contemporary sources from his time in Norway Brandt is called a merchant, clerk and literary figure. That he had a talent for visual art is not given much attention, even though rare examples of such activities are also found from when he lived in Norway.
His time as a natural science worker was probably Brandt's best period. He continued to be concerned about his family in Norway, and his plan was always to return. However, he was in debt in both worlds. His attempts at producing wine and liqueur in Brazil had an unfortunate outcome. Brandt appears to have been of an indecisive nature, easily blaming others for his problems.
He died in 1862 without ever returning to Norway. In Denmark and Brazil there is interest in Peter Andreas Brandt, and in the novel Veien til Lagoa Santa [The road to Lagoa Santa] (1981) Henrik Stangerup portrayed the life of the Danish-Norwegian partners in South America.
Recommended reading: Den forsvundne maler. P.W. Lund og P.A. Brandt i Brasilien [The vanished painters. P.W. Lund and P.A. Brandt in Brazil]. Museum Tusculanums Forlag, Københavns Universitet, 2004.