General Hendrik Merkus de Kock lifts the siege of Yogyakarta, the first major action of the Java War, on September 25, 1825.

The proximate cause is the Dutch decision to build a road across a piece of Prince Diponegoro's property that contained his parents' tomb.

Among other causes is a sense of resentment felt by members of the Javanese aristocratic families at Dutch measures intended to restrict the renting out of land at high prices.

Finally the succession of the throne in Yogyakarta is disputed: Diponegoro is the oldest son of Hamengkubuwono III, but as his mother was not the queen he is not considered to have the right to succeed his father.

Diponegoro's rival to the throne, his younger half brother, Hamengkubuwono IV, then his infant nephew Hamengkubuwono V, are supported by the Dutch.

Being a devout Muslim, Diponegoro is alarmed by the relaxing of religious observance at Yogyakarta court, the rising influences of the infidel Dutch in the court, as well as by the court's pro-Dutch policy.

The forces of Prince Diponegoro had been successful in the early stages of the war, taking control of the middle of Java and besieging Yogyakarta.

The Javanese population is supportive of Prince Diponegoro's cause, whereas the Dutch colonial authorities are initially indecisive.

The Javanese peasantry has been adversely affected by the implementation of an exploitative cultivation system, which requires villages to grow export crops to be sold to the government at fixed prices.

As the Java war becomes prolonged, Prince Diponegoro has difficulties in maintaining the numbers of his troops.

The Dutch colonial army, however, is able to fill its ranks with indigenous troops from Sulawesi, and later on with European reinforcements from the Netherlands itself.