March 17th is St Gertrude's Day. Gertrude was the Patron Saint of cats.
Her father was Mayor of the Palace for King Dagobert the First of France, and Gertrude was great-great-aunt of Charlemagne. She turned down an arranged marriage at the age of 10, and was installed as Abbess of Nivelles, in a convent her mother started, at age 20.
She was as good as a barn cat at getting rid of the mice in the harvested grain, which is how she became associated with cats and against mice.
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