Which supernova event listed in historical records was the last one seen within the Milky Way galaxy?

Answer

Kepler's Supernova (AD 1604)

Kepler's Supernova, observed in AD 1604, is specifically noted in historical records as the last supernova seen in the Milky Way.

Which supernova event listed in historical records was the last one seen within the Milky Way galaxy?
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