Causes
The Chilean civil war grew out of political disagreements between the president of Chile, José Manuel Balmaceda, and the Chilean congress. In 1889, the congress became distinctly hostile to the administration of President Balmaceda, and the political situation became serious, at times threatened to involve the country in civil war. According to usage and custom in Chile at the time, a minister could not remain in office unless supported by a majority in the chambers. Balmaceda found himself in the difficult position of being unable to appoint any ministers that could control a majority in the senate and chamber of deputies and at the same time be in accordance with his own views of the administration of public affairs. At this juncture, the president assumed that the constitution gave him the power of nominating and maintaining in office any ministers of his choice and that congress had no power to interfere.
The Congress was now only waiting for a suitable opportunity to assert its authority. In 1890, it came to light that President Balmaceda had decided to nominate a close personal friend as his successor. This brought matters to confrontation and the congress refused to approve a budget for supplies to run the government. Balmaceda compromised with congress, agreeing to nominate a cabinet to their liking on condition that the budget would be approved. This cabinet, however, resigned when the ministers understood the full scope of the conflict between the president and congress. Balmaceda then nominated a cabinet not in accord with the views of congress under Claudio Vicuña, whom it was no secret that Balmaceda intended to be his successor, and to avoid opposition to his actions, refrained from summoning an extraordinary session of the legislature for the discussion of the estimates of revenue and expenditure for 1891.
Read more about this topic: 1891 Chilean Civil War