Pieter Simon Hamel

After the Netherlands sold their possessions on the Gold Coast to the United Kingdom in April 1872, Hamel was employed at the consulate that the Netherlands had established at Elmina. Hamel first was appointed vice consul under consul Willem Le Jeune in 1873, before becoming acting consul on 15 March 1874, upon Le Jeune's return to the Netherlands. In May 1875, Hamel was subsequently installed as full Consul. On 5 June 1876, Hamel paid the kostgeld still due to Asantehene Mensa Bonsu for the final years of Dutch presence in Elmina.[3] Following a European leave between November 1877 to March 1878, Hamel returned to Elmina and was awarded the personal title of Consul General.

The Netherlands had decided to keep a diplomatic post at Elmina primarily for the payment of pensions to the retired recruits of the Royal Netherlands East Indies Army. Other reasons included the safeguarding of Dutch trade interests and the exploration of the possibility to continue recruiting soldiers for the Royal Netherlands East Indies Army in Africa.[4] Hamel especially went at great lengths in trying to negotiate a deal with an African head to recruit these soldiers: after the British abolished slavery in the Gold Coast in 1874, slaves could no longer be manumitted by the Dutch government in return for an army contract, leading Hamel to try his luck in Dahomey, Grand Bassam and Assini, which stood under French protection. Hamel undertook a mission to Krindjabo, the capital of the Kingdom of Sanwi in contemporary Côte d'Ivoire, in which he found King Amatifou sympathetic to his proposal, but unwilling to do anything without the blessing of the French. France, however, did not allow this recruitment to take place. Upon his return from European leave, Hamel tried to negotiate a deal in Liberia, an independent country not under the protection of either France or the United Kingdom, to no avail.[5]

The Consulate General at Elmina was disbanded in February 1880. Hamel subsequently appointed Arthur Brun as honorary consul at Elmina and left the Gold Coast.

Hamel was then appointed Consul General at Bangkok, where he had to take over a badly functioning consulate that was previously headed by Consul J. Salmon, who had to leave his post after suffering from a nervous breakdown.[6] Hamel reduced the workload of the consulate by limiting the number of Chinese-Dutch citizens under its protection. On the instigation of Hamel, the consulate was upgraded to a consulate general, primarily because of the trade links of Siam with the Dutch East Indies.[7]

In June 1887, Hamel was forced to leave his post because of failing health.[7]

After three years in the Netherlands, Hamel was appointed Consul General at Amoy for Southern China and Formosa in 1890. Hamel's main task was to secure the unimpeded migration of Chinese labourers from the Southern Chinese cities to the Dutch East Indies and the other Dutch colonies. Coincidentally, the Consul General in Beijing, Hamel's direct superior, was the former Gold Coast governor Jan Helenus Ferguson.[8]

While in Amoy, Hamel suffered two strokes, which forced him to retire. Hamel was admitted to a psychiatric hospital in Bendorf am Rhein in Germany where he died on 13 October 1900.[2]