on 17 June 1920 he was made the commanding officer of the famous 28th Kaniów Rifles Infantry Regiment. For the rest of the Polish-Bolshevik War, he commanded the 19th Infantry and then 20th Infantry Brigades. For his service during the conflict, in 1922 he was promoted to the rank of colonel (with precedence of 1 June 1919). After the Peace of Riga had been signed, Thommée remained in the army and on 10 August 1921 he was made the commanding officer of the General Army Area Brześć. On 20 October 1922 he became the first officer of the Grodno-based 3rd Military Area Command (DOK III) and at the same time he started his studies at the Higher War School in Warsaw. On 1 July 1923 he was promoted to the rank of brigadier general, and on 15 August 1924 he became the commanding officer of the 15th Infantry Division stationed in Bydgoszcz. One of the most promising staff officers of his times, in 1926 he was sent to Paris, where he graduated from the prestigious Ecole Superieure de Guerre. Upon his return to Poland, he continued his service at various posts, including the command over the Toruń-based 8th Military Area Command (DOK VIII; 1934–1938) and then the Łódź-based 4th Military Area Command (DOK IV). Second World War At the outbreak of the Invasion of Poland, on 1 September 1939, Thommée assumed the command over the Piotrków Operational Group, one of Polish Army Corps within the Łódź Army. Renamed to Thommée Operational Group on 6 September, the unit was the only part of the Łódź Army not to suffer tremendous losses during the retreat from the borders. After Gen. Juliusz Rómmel left his army for Warsaw, Wiktor Thommée managed to reorganise the withdrawing forces of the Łódź Army and fight the battle of Cyrusowa Wola on 8 September, in which he defeated the German 10th Infantry Division. After the battle, on 13 September his forces moved to the Modlin Fortress, where Thommée assumed the command of the Modlin Army. Besieged, the forces under his command defended the area until 29 September. Due to lack of supplies, food and water, Gen. Thommée negotiated the capitulation of his forces under the condition that all the soldiers were to be treated as prisoners of war and were to be set free. Although initially the Germans honoured the treaty, on 7 November 1939, Thommée was