He fought in the Lithuanian–Soviet War and was the Chief of the General Staff of the Lithuanian Army from August 1920 to April 1921.

He studied at the St. Petersburg University but quit after one semester and joined the Imperial Russian Army in August 1899.

After graduation, he served in the Finnish Life Guards Regiment until October 1912 when he was assigned to the headquarters of the Amur Military District.

[2] However, he was dissatisfied with the offered post and decided to join the anti-communist Northwestern Army commanded by Nikolai Yudenich.

[3] In May 1919, on his way to Helsinki, he stopped in Kaunas where Antanas Merkys, Minister of Defence of Lithuania, offered him a position in the Lithuanian Army which sorely lacked experienced officers.

[1] He worked as a director of a cement plant in Šiauliai[5] and established a company that planned to import wine from France to Russia.

[5] He was promised a monthly sum of 500 Lithuanian litas and help to his family members who lived in Russia.

[1] His wife died in 1925 leaving their 10-year-old son in care of Kleščinskis' mother and aunt who lived in poverty.