Set against the backdrop of the social and political upheaval of the late 1800s in Europe, Mary is an unconventional and annoyingly intelligent woman struggling to alter the destiny and education of her gender – and still find love.

This does seem like a good backdrop for a story.

As for the logline, I am still not sure what the story is actually about.

1st: If altering her destiny is important to the plot then I would name specifically what her dreaded destiny is.

2nd: I would give her a positive goal. Does she want to be a doctor in a time women were traditionally nurses? That would be an example of her trying to alter her destiny with some specifics.

3rd: As for the time and setting, I would use the term ‘Victorian England’ because it says the same thing in 2 words that you used 16 words to describe. Keeping the word count low is a must for any logline.

4th: Most storys have an inciting incident. Everything is normal, then ‘boom’ and event happens which sets the story in motion. If there is such an event in your story adding that to the logline will help as well.

5th: Finally, you don’t need to name the characters unless they are historically famous. If a story is about Jesus, then ?you would name him, if your story is about Joe Schmo from Albuquerque then just say ‘an average guy’.

Now here would be an example of what I am talking about concerning specifics; remember, your logline will be different because your story is different. This is just an example:
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When her parents announce her arranged marriage, an unconventional teen in Victorian England must some how sabotage her pending nuptials all while secretly pretending to be a boy in order to receive her degree in medicine”
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Hope this helped, good luck with this!