He studied law at the University of Göttingen and at Heidelberg University, and earned a doctorate in 1830.

After a stay in Paris, he became a burgher of Hamburg in 1831 and practised as a lawyer.

From the 1830s, he held numerous public offices, and he was elected as a senator in 1855.

He also served as Second and First Mayor during the terms 1879/80, 1882/83, 1885/86, 1888/89 and 1891/92.

[1][2][3] Two grandsons by his son Gustav Petersen, Carl Wilhelm Petersen and Rudolf Hieronymus Petersen, also officiated as first mayors of Hamburg, the former between 1924 and 1929 and again 1932 and 1933, the latter from 1945 to 1946.