[1] His father was a government official and his mother was the daughter of Christian Reccard, professor of Theology at University of Königsberg, consistorial councillor and astronomer.

He showed promise in mathematics in high school and he went on to study at the University of Königsberg where his uncle, Karl Gottfried Hagen was professor of physics and chemistry.

[4] In 1819 he undertook the examination for surveyors (Landvermesserprüfung) and after graduating took a job as a junior engineer (Baukondukteur) in the civil service.

[11] Hagen played a decisive role in planning the development of numerous German rivers and harbors.

Hagen took leave from his post in the Ministry of Trade and became chair of the Commission for the port construction in the Jade Bight.

[12] In 1866 Hagen was promoted to chief director (Oberbaudirektor) in the Department of Hydraulic Engineering and chair (Vorsitzenden) of the section of public works in the Ministry of Trade (Baudeputation).

This role involved responsibility for large water and harbor works in Prussia and other German States.

[1] Hagen died in 1884, his tomb is located on the Invalidenfriedhof Berlin, Scharnhorststraße near the main railway station.

On 7 April 1842 Hagen was elected as a member of the Royal Prussian Academy of Sciences, Berlin on the recommendation of Alexander von Humboldt.

In 1881 he was made a Freeman of Pillau On 2 May 1883 he was awarded a gold medal for extraordinary services to the construction industry.