Oath crisis

After the Act of 5 November the Germans wanted to build a Polish Armed Forces under Beseler's command, with the Legions as its core. The oath bound soldiers to loyalty to a future king and to brotherhood in arms with the German and Austro-Hungarian armies. Piłsudski held that a Polish army could swear only to a Polish government, and on 2 July 1917 he left the Provisional Council of State. On 9 and 11 July some 5,000 soldiers and more than 160 officers refused; the oath was taken mainly by part of the II Brigade.

The Germans treated the refusal as insubordination. Officers from the Kingdom were interned at Beniaminów and the rank and file at Szczypiorno, while legionnaires from Galicia were drafted into the Austro-Hungarian army. On the night of 21–22 July Piłsudski and Kazimierz Sosnkowski were arrested, and in August the Provisional Council of State fell apart. The crisis ended Piłsudski's cooperation with the Central Powers and strengthened his legend.