Serrata del Maggior Consiglio

The Great Council Lockout (Italian: Serrata del Maggior Consiglio) refers to the constitutional process, started with the 1297 Ordinance, by means of which membership of the Great Council of Venice became an hereditary title. Since it was the Great Council that had the right to elect the Doge, the 1297 Ordinance marked a relevant change in the constitution of the Republic. This resulted in the exclusion of minor aristocrats and plebeian from participating to the government of the Republic. Although formerly provisional, the Ordinance later became a permanent Act, and since then it was disregarded only at times of political or financial crisis (e.g. after the war against the League of Cambrai).

When the Commonwealth of Venice was formed, the Doge was assisted by a Council of Wise Men (Consilium Sapientium) elected by the people's assembly (Concio). Once obtained sovereign power in 1172, such Council came to be known as Great Council. It originally functioned as an extension of the people's assembly, and its members were elected on a yearly basis, with the general election usually falling on the day of Saint Michael (29 September). Later, in 1207 the election system was changed: the Concio was required to elect three representatives (up to seven since 1230), who had the duty to nominate the Councillors.

Over the years, the Great Council became the bone of contention between the people's party, which aimed to preserve the status quo, and the aristocratic party, which aimed to exclude up-starters from the government. On 5 October 1286, during the government of Doge Giovanni Dandolo, the aristocratic party presented a bill to reform the eligibility criteria for the Great Council, with the purpose of limiting its members to those who had already joined the Council or those whose paternal relatives held the position of Councilman. The proposal also demanded that candidates without family credentials could run for a position only upon joint approval on behalf of the Doge, the Minor Council, and the Council of Forty (Quarantia). After such bill was repelled, another bill was proposed, which required new entrants to be subject to approval on behalf of outgoing Councilmen. However, even this proposal was rejected.

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