On 14 October 1945, several months after Indonesia proclaimed its independence, Oerip was declared the chief of staff and interim leader of the newly formed army. Working to build a united force from the fractured former military groups in the country, Oerip received little oversight owing to irregularities in the chain of command. On 12 November 1945 General Sudirman was selected as leader of the armed forces, while Oerip remained as chief of staff. The two oversaw almost three years of development during the Indonesian National Revolution, until Oerip resigned in early 1948 because of the political leadership's lack of trust in the army. His health deteriorated; he was already suffering from a weak heart, and he died of a heart attack a few months later. He was posthumously promoted to full general.