In 1910 the German Reichstag developed a plan to relocate the Duala people living along the river, to be moved inland to allow for wholly European riverside settlements.

Manga Bell turned to other European governments for aid, and he sent representatives to the leaders of other Cameroonian peoples to suggest the overthrow of the German regime.

Sultan Ibrahim Njoya of the Bamum people reported Bell's actions to the authorities, and the Duala leader was arrested.

Manga Bell was made Ein-Jähriger, indicating that he held a certificate for education beyond the primary level but below the Abitur earned for completion of secondary studies.

In Manchester, he met the mayor at town hall and was mentioned in the October edition of the African Times (where the editor doubted that he and his father were actual royalty).

[6] Manga Bell inherited an 8,000 mark pension,[7] cocoa and timber interests in the Mungo River valley, property and real estate in Douala,[8] and a lucrative position as head of an appeals court with jurisdiction over the Cameroon littoral.

[10] Rudolf Duala Manga Bell was forced to rent buildings to European interests and move his own offices inland to the Douala neighbourhood of Bali.

The Germans outlined a plan to relocate the Duala people inland from the Wouri River to allow European-only settlement of the area.

[15] Manga Bell and the Duala requested permission to send envoys to Germany to plead their case, but the authorities denied them.

[20] In secret, Manga Bell sent Adolf Ngoso Din to Germany to hire a lawyer for the Duala and pursue the matter in court.

[21] The desperate yet motivated Manga Bell, turned to other European governments and to the leaders of other African ethnic groups for support.

[24] In Bulu lands on the other hand, Martin-Paul Samba agreed to contact the French for military support if Manga Bell petitioned the British.

"[27] On 6 May 1914 Bezirksamtmann Herrmann Röhm wrote to the Kuti Agricultural Station (where Manga Bell's envoy was being held), We are not confronted with any direct danger of some kind of violent action by the Duala.

For now the main value of the statements from Ndane [the envoy to Njoya] lies in the fact that they contain material for proceeding against those chiefs who are guilty of actual deliberate agitation in refusal of the expropriation and of resistance that reaches all the way over to Germany.

[36] His story became legend[4] and came to represent "the myth of extreme colonial oppression, based upon the catastrophic climax of German rule in Douala".

[41] Cameroon faced a long civil war when the outlawed nationalist Union des Populations du Cameroun political party in the 1950s and '60s waged its maquis against French and Cameroonian forces.

As a result, overt nationalist sentiment was shunned and figures such as Manga Bell were largely forgotten or only briefly treated in history books.

However, signs show that is coming to grips with its nationalistic past;[42] for example, in March 1985 the École Militaire Inter-Armes, part of the military of Cameroon, named a graduating class of cadet officers after Manga Bell.

[45] From April 14, 2021 to December 31, 2022, the Museum am Rothenbaum (MARKK) is presenting the multimedia exhibition "Hey Hamburg, do you know Duala Manga Bell?