Douwes Dekker, he was a strong political proponent of association between Indo-Europeans and Indonesians in the colonial Dutch East Indies and early post-colonial Indonesia.

Although Indos were part of the European legal class its lingua franca and much of its practices and beliefs were derived from its indigenous maternal lineage.

From their historic role as indispensable intermediaries and change agents, the Indos were increasingly reduced to a marginal position in colonial society.

[2] Simultaneously the Dutch Ethical Policy created an educated indigenous elite increasingly voicing the idea of Indonesian national independence.

Throughout the Japanese occupation of the Dutch East Indies in World War II and the following Indonesian revolution the existing estrangement between the native Indo-European population and indigenous peoples only widened and intensified.

In contrast the Eurasian community in neighbouring Malaya, that was hectored and admonished in the same way as the Indos in the 'Japanese East Indies', but that did not constitute any serious problem for the Japanese occupier.

Overall the majority of Indos remained fiercely proud of their European roots and opposed both Japanese and Indonesian attempts to denounce their western identity.

The older Dahler, who was known to be a quiet and amiable man, did not take a liking to the militant and sometimes harsh approach of the newcomers, but was unable to temper it, as Van den Eeckhout was being directly instructed by the Japanese.

Together with independence leaders Sukarno and Sjahrir he continued to groom Indos to join the national revolution, but their efforts were undone by extremist revolutionary forces during the violent Bersiap period.

Ironically in an effort to reduce repatriation of Indos to the Netherlands the Dutch government now actively promoted Indonesian citizenship for Indo-Europeans, the very idea Dahler had always fought for.

Dahler's tireless efforts to persuade Indo-Europeans to associate themselves with the indigenous peoples were often misconstrued as acts of betrayal, causing much resentment among his fellow Indo compatriots.

Max Rooyackers, a student from Sanata Dharma University, stated that Dahler's conversion was a symbolic one and was meant as an expression of assimilation and support for Indonesian nationalism.