https://cs.wikipedia.org/wiki/Soubor:Marie_Curie_signature.s...
The nobel prize of 1903 refers to her as "Marie Curie, née Sklodowska", meaning that Sklodowska is her maid name but not her name after marriage in French.
The country didn't exist at the time, being partitioned between Prussia, Russia and Austria-Hungary. Poles didn't have much to say about the university admission policies of the Russian Empire, where she lived. She did, however, attend the so called Flying University [1], which was a higher education institution organized by Polish underground resistance.
Heck, she event has a SI unit named after her, the Curie.
2. The Curie isn't an SI unit, the Becquerel (Bq) is.
and named the first element she discovered - Polonium - after her homeland.
And in Russian space she is Мария Склодовская-Кюри (Maria Skłodowska-Curie) too (that was on her portrait in our chemistry class back in 198x for example).