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what is wrong with ragnar's last son
In the 2013 TV series Vikings, because Ragnar did not heed Aslaug's warnings, Ivar was born with weak bones, his legs twisted and seemingly broken.
what is the 2013 tv series vikings based on
The 2013 TV series Vikings is inspired by the sagas of Viking Ragnar Lothbrok.
when does thr 2013 tv series vikings take place
The 2013 TV series Vikings begins at the start of the Viking Age, marked by the Lindisfarne raid in 793.

Question: what years was the period
Self-contained rewrite: what years was the viking age