Such views and Pan-Slavism, which they shared with the other moderate right-wing parties, drove them into very hostile attitude towards Germany and Austria-Hungary during the World War I,[7][3][4][5][6] and by 1917, they were strongly nationalist and defensist;[24] during the Russian Civil War, they became proponents of military dictatorship and territorial integrity of the Russian Empire, and were the strongest supporters of the Whites next to the nationalist parties.

They interpreted their electoral win as a mandate and allied with the left-leaning peasant Trudovik faction, forming a majority in the Duma.

The appeal failed to have an effect on the population at large and proved both ineffective and counterproductive, leading to a ban on its authors, including the entire Kadet leadership, from participation in future Dumas.

Finnish liberal politician and professor of jurisdiction and politology Leo Mechelin was expelled 1903–1904 when the Kadets were preparing to form a party.

Although excluded from the more important Duma committees, the Kadets were not entirely powerless and could determine the outcome of certain votes when allied with the centrist Octobrist faction against right-wing nationalist deputies.

With the revolution crushed by 1908, they moderated their position even further as they voted to denounce revolutionary violence, no longer sought confrontation with the government and concentrated on influencing legislation whenever possible.

In 1910, the government rekindled its pre-revolutionary Russification campaign in an attempt to restrict minority rights, notably drastically curtailing Finland's autonomy.

However, a minority of Kadets headed by Pyotr Struve supported a moderate version of Russification, which threatened to split the party.

Kadet leaders on the left like Central Committee member Nikolai Vissarionovich Nekrasov argued that the Duma experience had been a failure and that "constructive work" was pointless under an autocratic government.

As Russia's defeats in the war multiplied, the Kadets' opposition became more pronounced, culminating in Miliukov's speech in the Duma in October 1916 when he all but accused government ministers of treason.

The Kadets' position was further eroded during the July crisis when they resigned from the government in protest against concessions to the Ukrainian independence movement.

Sergei Fedorovich Oldenburg was Minister of Education and served briefly as chair of the short-lived Commission on Nationality Affairs.

However, the party soon drifted into hardline nationalist politics and joined the national-communist National Salvation Front and supported the Supreme Soviet against President Yeltsin.