Armed Forces Day (Poland)

Armed Forces Day, known also as the Feast of the Polish Armed Forces (Polish: Święto Wojska Polskiego), is a national holiday celebrated annually on 15 August in Poland, commemorating the anniversary of the 1920 victory over Soviet Russia at the Battle of Warsaw during the Polish–Soviet War. Armed Forces Day is held in conjunction with the Day of the Assumption of the Virgin Mary, itself a separate public holiday.

Source: Wikipedia — Armed Forces Day (Poland) (CC BY-SA 4.0)