27, Finnish: Kuninkaallinen preussilainen jääkäripataljoona 27) was a jäger battalion of the Imperial German Army during World War I.

The recruitment of the Jäger volunteers from the Russian Grand Duchy of Finland had to be secret, and was dominated by German-influenced circles, such as university students and the upper middle class.

The recruits were transported across Finland's western border via Sweden to Germany, where the volunteers were formed into the Royal Prussian 27th Jäger Battalion.

On 9 May 1916, the Lockstedt training group (Ausbildungs-Truppe-Lockstedt) was designated the Royal Prussian Jaeger Battalion number 27 (Königlich Preussisches Jägerbataillon Nr.

This did not happen as there was no political initiative for this in Finland or in Germany, which were preparing for a separate peace with the Russian Empire in order to fight more effectively on the Western Front against France and the United Kingdom.

27), which was used with relatively modest losses to attain experience, but also re-trained for the more technically demanding duties of artillery, engineers, supplies, etc.

The Jaeger Battalion participated in the ranks of the 8th German Army from 1916 in the battles of World War I on the northern flank of the Eastern Front.

The master sergeants (Fäbel) were Perper and Steinmuller, and the non-commissioned officers in lower ranks (Unteroffiziers) were Claussen, Huyssen, Hoden and Toeppel.

The pioneer non-commissioned officer Claussen and machine gun trainer Huyssen continued to serve during the 27th Battalion period and became lieutenants.

Captain Toivo Kuisma died in the Aunus attack in 1919, and Major Sven Weckström in 1921, having been wounded in Maaninkajärvi that year.

Captain Toivo Kuisma died in the Aunus attack 1919 and Major Sven Weckström in 1921, having been wounded in Maaninkajärvi that year.