The Separate Battalion's core were the 5th and 6th Infantry Companies and the 2nd Hussar Squadron that were detached from Kaunas' komendantūra.

On March 28, these were joined by the Kaunas' training team's soldiers of the 1st and 4th Company, in addition to several volunteer machine gunners from Vilnius.

[2] Their armament was 8 machine guns, 686 rifles, 120 pistols and revolvers, about 104,000 rounds of ammunition.

After battles with the Soviet Russian Army ceased, the unit was dislocated in Žiežmariai.

[2] Battalion III was formed in January 1920 from the Pasvalys Kommandantur and from the recruits of Telšiai County.

[2] On 7 February 1920, the 5th Infantry Regiment was given the name of the Grand Duke of Lithuania Kęstutis.

[2] The regiment possessed 34 machine-guns, 1,780 rifles, 133 carbines, 64 pistols and revolvers, 133 bayonets, 149 horses and other military equipment.