He was delegate at the First All-Belarusian Congress in 1917 and member of the Council of the Belarusian Democratic Republic.

In December 1919 Krecheuski was elected President of the Council of the Belarusian Republic and served on this post till his death.

In exile in Prague since 1919, he organized active information campaigns for Western governments about the current states of Belarusian SSR and West Belarus.

Krecheuski convinced the Czechoslovak government to give grants for Belarusian students.

He created the Belarusian archive in Prague and published the politological almanac Zamiežnaja Biełaruś.