After the Dutch captured the capital during Operation Kraai on 19 December 1948, Soegijapranata ordered that the Christmas festivities be kept simple to represent the Indonesian people's suffering. During the Dutch occupation Soegijapranata smuggled some of his writings out of the country; the works, later published in "Commonweal" with the help of George McTurnan Kahin, described Indonesians' daily lives under Dutch rule and called for international condemnation of the occupation. Soegijapranata further opined that the Dutch blockade on Indonesia, aside from strangling the new country's economy, increased the influence of its communist groups. After the Dutch retreated in the wake of the General Attack of 1 March 1949, Soegijapranata began working to ensure Catholic representation in the government. With I. J. Kasimo, he organised the All-Indonesia Catholic Congress (). Held between 7 and 12 December, the congress resulted in the union of seven Catholic political parties into the Catholic Party. Soegijapranata continued his efforts to consolidate the Party after the revolution.