The Swedish tactics had worked incredibly well up until Poltava, and then the entire continental army was lost in a single battle. Where did the battle go wrong?
Bonus! What the hell happened to all of the prisoners? That's a shit ton of people to have to imprison. I know they were pressed into building or rebuilding a nearby city, but what then? Were they imprisoned forever? Worked to death? Pressed into the Russian Army? Any hope of release?
Where did the battle go wrong?
Strategically - when Karl became overconfident and dared to attack Peter forces (which outnumbered his) in defensive position. Swedish tactics worked well until russian soldiers weren't drilled well enough and coordination between branches was poor. As soon as artillery, infantry and cavalry started to work coherently on well-determined goals, infantry was trained to keep line and shoot quick volleys, swedes started to lose. You could read about Peter's effort to overhaul army after 1700 disaster at Narva and how he created new army in [1].
First bell was battle at Lesnaya - so it wasn't a 'single battle'. BTW, Lesnaya contributed greatly to Poltava's result - as large supply convoy was destroyed - so it was called in early imperial history texts a mother of Poltava.
For detailed battle analysis see [4,5]. Some important tactical factors:
commanding and communication issues - orders weren't reaching in time or at all
swedes fought in reversed front
a line of russian redoubts magnified sweden issues with C&C and caused major delay in attack
Lewenhaupt followed battle plan to letter and rejoined the army instead of attacking the camp
russian artillery proved to be effective and was severely underestimated by Karl
Bonus! What the hell happened to all of the prisoners? That's a shit ton of people to have to imprison. I know they were pressed into building or rebuilding a nearby city, but what then? Were they imprisoned forever?
Sent for settlement in South-East Russia and Siberia in 1710 and then 1711. Some were settled near Poltava in separate villages - see [2]. Many eventually returned back to Sweden - after Nystadt Treaty - see [3]. Some stayed - villages Oslino and Seryukovo near Tobolsk were founded by swedish POWs, who stayed. Till late 19 c, there were active scrimshaw masters (descendants of swedes) in Tobolsk city - and they worked with mammoth bone.
Worked to death? Pressed into the Russian Army? Any hope of release?
Per Article 14 of Nystadt Peace Treaty, ratified by Aug 1721, all POWs or resettled civilians from both sides could return to their home immediately and without any ransom (at that time ransoms for POWs were quite common). They are also free to stay if they choose.
Here's excerpt in russian (full text - see [3]):
14 С обеих сторон военные пленники, какой бы нации, чина и состояния ни были, имеют тотчас по воспоследованной ратификации сего мирного трактата без всякого выкупа, однако ж когда всякий наперед либо во учиненных каких долгах, или разделку учинит, или в платеже оных довольственную и справедливую поруку даст, из плена освобождены, на совершенную свободу выпущены и с обеих сторон без всякого задержания и в некоторое уреченное по расстоянию мест, где оные пленники ныне обретаются, пропорциональное время до границ с надлежащими подводами безденежно по возможности выпровождены быть. А те, которые у одной или другой стороны службу приняли или инако в землях одной или другой стороны остаться намерены будут, в том без изъятия всякую свободу и совершенную мочь иметь. Сие же разумеется и о всех во время сей войны от одной или другой стороны увезенных людях, которые також по своему произволу остаться или в дома свои свободно и без помешательства возвратиться могут и имеют, кроме тех, которые по своему желанию веру греческого исповедания приняли, которые на стороне е.ц.в. остаться имеют; для чего обе высокодоговаривающиеся стороны в своих землях публичными указами о сем публиковать и объявить изволят.
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