In 1917, Ćvikievič became one of the founders of a Belarusian society in Moscow and later that year participated in the
First All-Belarusian Congress. In January 1918, the executive committee of the Congress sent him and
Symon Rak-Michajłoŭski to Brest for peace talks. However, they could not secure admission to participate in the talks as a separate Belarusian delegation (admission was blocked by
Leon Trotsky) and instead joined a delegation from the
Ukrainian People's Republic as advisers. In March 1918, he was sent to
Kiev as part of a diplomatic mission, during which Ćvikievič resolved open issues of the Belarusian-Ukrainian border, sought recognition of the
Belarusian statehood and revision of the
Brest Peace, and approached diplomatic missions of other countries for financial assistance to the
Rada of the Belarusian Democratic Republic. He was also actively involved in the publication of the Belarusian newspaper "Belarusian Echo" in
Kyiv and the establishment of a Belarusian chamber of commerce in that city. In May 1918, the Belarusian mission addressed a Russian peace delegation and handed over a note signed by Ćvikievič and
Mitrofan Dovnar-Zapolsky to the delegation's head
Rakovsky, urging the Russian Soviet government to recognise the independence of Belarus. In the spring of 1919, the
Rada of the Belarusian Democratic Republic sent Ćvikievič on a diplomatic mission to Berlin and then to Vienna. From 1921 to 1923, he held the post of Minister of Foreign Affairs in the
Rada of the Belarusian Democratic Republic in exile and chaired the First All-Belarusian Conference in Prague in September 1921. In 1923, he replaced
Vaclaŭ Lastoŭski, as new head of the
Rada of the Belarusian Democratic Republic and was based in
Kaunas. == Return to Soviet Belarus and persecution ==