Britain declared war on Germany on 3 September, still hoping for a peaceful settlement after the invasion of Poland two days earlier. Poland had been taken unawares by the brutal German strategy of Blitzkrieg, with both Luftwaffe attacks and land advances leaving a trail of devastation. By 6 September, Polish forces were being pushed towards the German border when the northern and southern advances linked up at Lodz in central Poland. Pockets of Polish forces were forced to surrender around Poznan, Pomerania, Lodz and Krakow. Following the secret Nazi-Soviet Pact, the Red Army then invaded from the east on 17 September, meeting German forces near Brest-Litovsk on 20 September. Warsaw withstood 18 days of continuous bombing, not surrendering until 27 September. Despite mobilizing one million men, the mechanized German army outmatched the Poles on every level and, with little help from Britain and France, Poland easily and quickly fell into German and Russian hands.
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