I recently completed an M2 (second year of masters) in mathematics in a Paris university. I come from the UK, had never studied French until the summer directly before, and foolishly thought that taking courses in a different language would be an interesting challenge. I was admitted to the course without needing to take any language competency exams. All lectures and learning material were in French, but we were allowed to write exams in English (which I did).
I absolutely bombed the first semester, achieving a 10.5/20 (~50th percentile), which is not great, and I felt that it was at least partially due to the language barrier (though I did lack some mathematical maturity compared to French ENS students in the course). I managed to get 18.5/20 in my second semester, which is considerably better. So I finished with a 14.5/20 (or grade bien), which was respectable (in the top 15% of my course) but I don't know if it will be good enough for the competitive PhD programs that I was hoping to apply to next year. It is perhaps worth noting that I maintained excellent grades during my UK undergraduate years.
My question is; would those PhD programs be willing to view my second semester grades (which include my thesis) as more reflective of my potential than those of the first semester? In other words, are (self-inflicted) language difficulties considered to be mitigating circumstances?