Interesting you should ask about the notion of citizenship in Italy. The tumultuous path which led to the creation of the Kingdom of Italy catalyzed the creation of a self-contained but incredibly active Italian school of thought regarding concepts tied to the nation state. The most prominent writer is probably Pasquale Stanislao Mancini, a Neapolitan jurist and Italian patriot, however all through the 19th century Italian jurists developed a number of principles to which they associated nationality, which they used to elaborate the concept of a national Italian citizenship on which to base the struggle for national unity. Post-unity, prominent Italian legislators like Santi Romano and Vittorio Emanuele Orlando built on Mancini's writings on national citizenship to mold the body of law which currently regulates Italian citizenship.

Mancini presented his legal and philosophical arguments for the first time during a lecture he held at the University of Turin in 1851, where he sought refuge after the second initiative to institute a parliament in the Kingdom of Naples (of which he was one of the chief architects) was squashed violently. In his lecture, he does not distinguish between the concepts of citizenship and nationality; arguing instead that nationality is reciprocally linked linked to the possession of citizenship, and both are legal constructs are necessary to bind individuals to the state. At this point in time, Mancini is only really talking about civil rights; he does not consider voting rights and participation in politics elements of citizenship, probably because they are not necessary to identify a group people under the more common definitions of nationality. This fits in well with the Statuto Albertino, the constitution of the Kingdom of Piedmont adopted in 1848, which in spite of guaranteeing legal and judicial rights, with regards to enfranchisement only stipulated an upper legislature composed of individuals appointed by the King and a lower legislature elected by literate of-age males able to pay a poll tax. See how that works? This is the gist of what the emergent mid-19th century notion of citizenship meant to Italian legal academics.

Mancini's argument, although itself an elaboration of concepts already introduced by in jurists like Giandomenico Romagnosi and Lucanmario Pagano, provided a convenient ideological and juridical ground which the sponsors of the Risorgimento used to justify the unification of Italy.

According to Mancini, because Italians were aware of their national identity, they had the right to fight to create a state enshrining the nation they felt they were a part of. Stretching this argument, the logical conclusion is that every nation should have the right to an independent existence. The concept of nationality is therefore the justification of state sovereignty, as well as the basis for its recognition by other states. In the Mancinian understanding of citizenship, this is the foundation of the relationship between citizen and government: The nationals of a nation, once they belong to a nation-state, are subject to its authority. Kind of cool, right?

This, in post-unification Italy, legal philosophy recognized the citizen as he who belongs to the state. Consequently, the series of rights and duties established by the Italian constitution are recognized to him.

This ties in well with the concept of the "Liberal State" pervasive in European political thought in the 19th century. Article 24 of the Statuto Albertino, which upon the proclamation of the Kingdom of Italy in 1861 mutated into the Italian Constitution, affirms: "All subjects, whatever their title or rank, are equal before the law. They all enjoy civil and political rights, and are eligible for civilian and military appointments, subject to the exceptions established by law. "

Thus "citizens" are "subjects;" in short, those who are subject to the authority of the King, the personification of the State. The citizen enjoys civil and political rights within the confines established by the law. Ergo, the law and lawgivers empower citizenship.

Now, to specifically answer your question: the Grand-Duchy of Tuscany in 1860 had no constitution, and as such no legislative framework regulating the relationship between government and governed, or citizenship for that matter. The Duke Leopold had indeed worked towards introducing one back in 1790, however efforts were abandoned after his elevation to the throne of the Holy Roman Empire following his brother's death. In spite of the lack of a formal constitution, the lives of the Grand Duchy's citizens were far from unregulated: Tuscany had a well-developed and elaborate legal system. This isn't to say the system was perfect; lack of codification led to overlapping and unaligned norms, rules, and decrees, which could create confusion and uncertainty. In 1786 the Duke Leopold completed an extensive overhaul of the legal system, constructed by streamlining a catalog of every law passed in Tuscany between 1444 and 1778 compiled by his prime minister at the time, Angelo Tavanti. However, Tuscany remained miles behind more legislatively well-developed states, like France, England, or even Piedmont.