{"id":1066,"date":"2010-01-01T09:20:00","date_gmt":"2010-01-01T07:20:00","guid":{"rendered":"https:\/\/bronicable.com\/en\/uncategorized\/on-this-day-in-bulgaria-september-20\/"},"modified":"2026-07-16T19:39:34","modified_gmt":"2026-07-16T17:39:34","slug":"on-this-day-in-bulgaria-september-20","status":"publish","type":"post","link":"https:\/\/bronicable.com\/en\/on-this-day-in-bulgaria\/on-this-day-in-bulgaria-september-20\/","title":{"rendered":"On This Day in Bulgaria: September 20"},"content":{"rendered":"<p>Every day in Bulgarian history holds a story worth remembering. In this recurring series, <strong>On This Day in Bulgaria<\/strong>, we look back at notable events, decisions, and milestones that happened on this date across the country&#8217;s history.<\/p>\n<h2><strong>September 20, 917 \u2014 Battle of Achelous<\/strong><\/h2>\n<p>In one of the grandest military engagements of the European Middle Ages, Bulgarian Tsar Simeon I the Great scored a decisive victory over the Byzantine Empire at the Achelous River (near modern-day Pomorie). The annihilation of the Byzantine army established Bulgaria as the dominant military power in Southeastern Europe.<\/p>\n<h2><strong>September 20, 1944 \u2014 Bulgaria Declares War on Hungary<\/strong><\/h2>\n<p>Following the change of government and shift to the Allied side, the new Bulgarian administration declared war on Hungary. Bulgarian military divisions were integrated into the Red Army&#8217;s 3rd Ukrainian Front, participating in the Belgrade Offensive and campaigns in Hungary and Austria to push German forces out of Southeastern Europe.<\/p>\n<p>Explore more of Bulgaria&#8217;s story on <strong><a href=\"https:\/\/bronicable.com\/en\/\">Bronicable<\/a><\/strong>, including our <strong><a href=\"https:\/\/bronicable.com\/en\/category\/from-above\/\">Bulgaria From Above<\/a><\/strong> series and our guides to <strong><a href=\"https:\/\/bronicable.com\/en\/category\/bulgaria\/\">the best of Bulgaria<\/a><\/strong>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>On this day in Bulgarian history: Tsar Simeon I defeated the Byzantines at Achelous in 917, and Bulgaria declared war on Hungary in 1944.<\/p>\n","protected":false},"author":1,"featured_media":889,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[32],"tags":[],"class_list":["post-1066","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-on-this-day-in-bulgaria","latest_post"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.0 - 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