Can someone help me understand the documents, I might need in this case. My maternal grandfather was born in France but never lived there. I have just located his French Birth Certificate. It states that his father, my great grandfather was born in Italy. I have my grandfather's petition for naturalization. His petition for citizenship took place when my mother was 10 years old. In the petition, my grandfather appears to be considered as a dual citizen of France and Italy. The document asks him to renounce his allegiance to the Republic of France and Victor Emmanuel III, King of Italy.
Can someone advise me on what I might need? For example, would I also need my great grandfather's birth certificate showing that he was born in Italy. My grandfather's French birth certificate states that my great grandfather was "ne a Positano Italia" born in Positano, Italy.