Samkalden worked as a civil servant for the Ministry of Colonial Affairs in Batavia in the Dutch East Indies from September 1938 until April 1942.

Following the end of World War II Samkalden moved to Surabaya but was arrested during the Indonesian National Revolution.

Samkalden was released on 13 November 1945 and moved back to the Netherlands and worked as civil servant for the Ministry of Justice from September 1946 until June 1947.

Samkalden worked as a researcher and associate professor of Constitutional law at the Leiden University June 1947 until February 1948.

Samkalden also became active in the public sector and worked as a professor of International relations and Leiden University from May 1959 until April 1965.

Asser Instituut, Anne Frank Foundation and the Royal Academy of Arts and Sciences) and served on several state commissions and councils on behalf of the government (Onderwijsraad, Probation Agency and the Raad voor Cultuur).