In the summer of 1919, when Pskov was briefly occupied by the Estonian Army, Bellen fled from the advancing Bolshevik Red Army with his wife and sons and settled in the newly independent Estonia. In Estonia, the family changed the nobiliary particle in its name from the German "von" to the Dutch "van", because the German noble particle, used by many of the Russian nobility, was specifically banned by law in Estonia as an indication of Russian nobility.