In 1804 the provisional government decreed that all of the papers from the governments of the suppressed Republic of Lucca were to be brought together at a single institution. This was the origin of the State Archives. In 1860 the secret archives of the Duchy of Massa and Carrara and the provincial one of Castelnuovo Garfagnana were transferred to the Lucca Archives. The documents in the Archives are divided into sections: Diplomatic, concerning the Republic, Napoleonic and Notarial.

The documentary material in the Diplomatic section includes 19,855 parchments (8th-19th centuries), arranged in chronological order and by provenance: from monasteries, from families of the nobility and from the secret archives of the City-State.

The documentary material on the Republic, conserved organically from the beginning of the 14th century, includes statutes, the proceedings of the Elders before the liberation, the proceedings of the Elders after the liberation, public amendments of the papers of the general curia, and the papers of the Guinigi government.

From the Archives of the Napoleonic government of Elisa Baciocchi Bonaparte and of the Bourbonic duchy come the civil list and property list of the princes, the senate, the council of state and council of ministers; ministries; secretaries of the governments; prefecture of Lucca; registry office; public health and hygiene; education, arts, industry, commerce and food office; water, roads and buildings; militia; police; the mint and public treasury; state property; register, mortgages and public debt; tax collectors.

Lastly, the Notarial Archives with the records of the nobility and private individuals, as well as special collections including documentation on congregations in the city and the territory, brotherhoods, and hospitals. The manuscripts in this section are considerable, including 246 pieces of notable historical importance.

Among the many documents of scientific nature in the Archives are records from the early years of the former Psychiatric Hospital of Fregionaia.