Hamina Cadet School was abolished in 1903 with the abolition of the separate Army of the Grand duchy of Finland as part of the Russification policy.
Finally it was settled that the Grand Duchy of Finland would fulfil its obligation to the common defence with a monetary compensation to the Russian Empire instead through the provision of conscripts.
Many of the officers from the Fredrikshamn Cadet school played an important part in the early independence movement of Finland; both in the administration of the Grand Duchy as well as in active support of the resistance.
Some other former Hamina cadets such as Carl Enckell, Rudolf Walden, and Hannes Ignatius would rise to the occasion, but their effect was due to individual abilities.
After the Whites' victory in that war, Mannerheim resigned as Commander-in-Chief, dismayed at the increasing German influence in Finnish military and political affairs.