In 1915–1919, Jaakson was a member of board of the Tallinn Municipal Bank (Estonian: Tallinna Linnapank).

In 1918, he was general commissioner of the Estonian Provisional Government for expropriating property from the German occupation powers.

In 1926–1940 he worked as president of the Bank of Estonia and was a member of the National Economic Council.

Jaakson was also a member of the National Council, the upper house of the bicameral parliament, in 1938–1940.

He was deported to Russia, accused of "counterrevolutionary activities", sentenced to death and executed in Sosva, Sverdlovsk Oblast, Soviet Union, in 1942.