As soon as he reached the rank of Lieutenant, he volunteered for service in the
Congo Free State of King
Leopold II of Belgium, and in 1887 he went out for a first term. He did so well in founding new stations north of the Congo that, when the government decided to put an end to the Arab domination on the Upper Congo, he was selected to command the chief expedition sent against the slave traders in the 'Congo Arab war'. The
Congo Arab war began in April 1892, and it was not brought to a successful conclusion until January 1894. The story of this war was narrated in detail by
Sidney Langford Hinde, who took part in it, in his book
The Fall of the Congo Arabs. The principal achievements of the campaign were the capture in succession of the three Arab strongholds at
Nyangwe,
Kasongo and Kabambari. For his services, Dhanis was awarded the noble title of
baron, and in 1895 was made vice-governor of the Congo Free State. == Later life ==