Second Madagascar expedition The Second Madagascar expedition ( French : " L ' Expédition de Madagascar " , or " Campagne de Madagascar " ) was a French military intervention which took place in 1894 - 1895 , sealing the conquest of the island of Madagascar by France . It was the last phase of the Franco - Hova War and followed the First Madagascar expedition ( 1883 – 85 ) . Background . Madagascar was at the time an independent country , ruled from the capital of Antananarivo by the Merina dynasty from the central highlands . The French invasion was triggered by the refusal of Queen Ranavalona III to accept a protectorate treaty from France , despite the signature of the Franco - Hova Treaty of 1885 following the First Madagascar expedition . Resident - general Charles Le Myre de Vilers broke negotiation and effectively declared war on the Malagasy monarchy . The expedition . An expeditionary corps was sent under General Jacques Duchesne . First , the harbor of Toamasina on the east coast , and Mahajanga on the west coast , were bombarded and occupied in December 1894 and January 1895 respectively . Some troops were landed , but the main expeditionary force however arrived in May 1895 , numbering about 15 , 000 men , supported by around 6 , 000 carriers . The campaign was to take place during the rainy season , with disastrous consequences for the French expeditionary corps . As soon as the French landed , revolts erupted here and there against the Merina government of Queen Ranavalona III . The uprisings were variously against the government , slave labor , Christianization ( the court had converted to Protestantism in the 1860s ) . As the French force advanced towards Antananarivo , they had to build a road along the way . By August 1895 , the French were only mid - way at Andriba where there were numerous Malagasy fortifications but only limited fighting . Disease , however , especially malaria , but also dysentery and typhoid fever , was taking a heavy toll on the French expeditionary corps . The expedition was a medical disaster : about 1 / 3 of the force died of disease . Altogether , there were 6 , 000 deaths in the expedition , four - fifths of them French . The Malagasy Prime Minister and Commander - in - Chief Rainilaiarivony tried to resist at Tsarasaotra on 29 June 1895 , and at Andriba on 22 August 1895 . He again attacked the Duchesne " flying column " in September , but his elite gunner troops were decimated by the French . Duchesne had to send a " flying column " from Andriba on 14 September 1895 , formed of Algerian and African soldiers as well as marines and accompanied by pack mules , to the capital . They arrived at the end of September . An artillery battery was trained on the royal palace from the heights around the capital , and high - explosive shells were fired on the palace , killing many . The Queen promptly surrendered . In the whole conflict , there were only a few skirmishes , and only 25 French soldiers died from fighting . Aftermath . The conquest of the island was formalized by the 6 August 1896 vote at the French National Assembly , which resulted in favor of the annexation of Madagascar . Despite the success of the expedition , the quelling of the sporadic rebellions would take another eight years until 1905 , when the island was completely pacified by the French under Joseph Gallieni . During that time , insurrections against the Malagasy Christians of the island , missionaries and foreigners were particularly terrible . Queen Ranavalona III was deposed on January 1897 and was exiled to Algiers in Algeria , where she died in 1917 .