Radama II, who succeeded Ranavalona in 1861, changed his political direction towards foreigners. He called the Europeans to Madagascar, authorizing them (1862) to colonize, to open schools and to preach the Christian religion; he welcomed the Catholic missionaries with pleasure, lavishing his favors on them, as did the Protestants to whom he gave the consent to build churches in various points of Tananarivo. But Radama II indulged in debauchery in the company of his favorites, who, not respecting the ancient customs of the ancestors, were guilty of numerous injustices, so that they aroused the general indignation, then kept alive by the prime minister and the senior officers of the kingdom., dissatisfied with being kept aloof. Things escalated to the point that a riot broke out, after which Radama himself was assassinated in the night from 11 to 12 May 1863: on that same day his widow, Rabodo, was proclaimed queen of Madagascar under the name of Rasoherina. During his reign it retained the freedom of worship instituted by Radama and the Europeans remained the right to live in Madagascar. On 1 August 1863, Commander Dupré brought the Franco-Malagasy treaty signed by Napoleon III, which the prime minister refused to accept. Lambert, who at that time was returning from France with many engineers, after having established, thanks to the regular consent of Radama, the Compagnia del Madagascar, a financial, industrial and commercial company, also had to give up his projects.
In 1883 Ranavalona II died and was succeeded by Ranavalona III. At the advent of the new queen, Admiral Galibier went to Tamatava and entered into negotiations with the Merina authorities, who had fomented some troubles among the Sakalava del Boina, subjected to the French protectorate, inciting them to raise the banner of Ranavalona in place of that tricolor. Unable to reach an agreement, Admiral Miot was sent to enforce the rights of France; he conducted military operations in the north-west and Vohémar which decided Imerina to recognize the French protectorate. Admiral Miot and the consul of France, Patrimonio, went to Tananarivo: the French who had been expelled in 1882 returned to their seats, and so did the missionaries; Le Myre de Vilers was named resident. But almost immediately, political difficulties arose around this protectorate and French rights which continued for many years in a latent form, until the day in which several French were assassinated: the French government was then forced to prepare for war, which in turn the government of Tananarivo did. To try to avoid this serious situation and renew an attempt at conciliation, Le Myre de Vilers was sent again on a mission to Tananarivo to submit a draft treaty to the prime minister, which was responded to with an unacceptable counter-proposal; the representative of France then left Tananarivo (October 17, 1894) together with all his compatriots, deeming any further discussion useless.
According to SPORTSQNA, this was equivalent to a declaration of war: a fact foreseen and desired in France, where since August a special commission had begun the study of an expedition to Tananarivo. Maiunga was chosen as a base, which made it possible to reach the capital by going up the Betsiboka and Ikopa rivers; as it turned out that the Hovas could have 25-30,000 men armed with modern rifles and 40-50 guns, a minimum of 12,000 men was deemed necessary. On December 7, 1894, parliament granted a credit of 65 million. The direction of the expedition was entrusted to gen. Duchesne, already distinguished at Tonkin.
The plan of operations concretized by Duchesne considered the carrying out of the expedition in several phases: 1. occupation of Maiunga (end of February) by the vanguard, establishment of the base and advance to Marovoay (80 km.); 2. landing of the command in chief (early May) and of the 1st brigade (6000 men) and advance of the command up to Mevatanana, while the corps of operations would be completed and a road opened; 3. subsequent advance in jumps by brackets on Tananarivo, which it was hoped to reach in early September.
Careful was the preparation of services and especially of health and transport. Preliminary operations were carried out for the defense of the colony of Diego Suarez, invaded since December 1894 by the Hova, and for the occupation of Tamatava, carried out on December 12, 1894 by a detachment of navy (550 men) for diversion purposes.
On January 14, 1895, Majunga was bombed by the naval division and occupied the following day.
From 10 to 24 March the avant-garde (Gen. Metzinger) landed at Majunga and the arrangement of the base began. On March 27, a detachment, supported by gunboats, seized the position of Mahabo, an outpost of the Hova on the left of Betsiboka. On 30 March a column of 4 companies with an artillery section gathered in Mevarano and moved the following day to Marovoay, but due to the marshy terrain they had to return, waiting for the end of the rainy season.
The expeditionary force was disembarked from March to May; on 29 airile, having sufficient forces, gen. Metzinger moved with 3 columns against the positions of Marovoay, defended by 3000 Hova, which were occupied on 2 May after weak resistance. From 15 to 17 May the positions of Ambolomonti were attacked and taken, garrisoned by 2000 Hova, who fled abandoning 60 dead, guns and ammunition.
The gen. Duchesne (who had assumed command on May 16) then ordered the vanguard to continue on to Suberbieville. On 26 May the gen. Metzinger moved from Ambatt with his troops (4 battalions and a battery) and ferried the river on 6 June upstream of the confluence of the Ikopa, on 9 he attacked and took Suberbieville: the Hova fled in disorder abandoning many weapons and ammunition.