The promissione ducale (lit. 'ducal promise'; Latin: promissio domini ducis) was an oath of office sworn by the incoming Doge of Venice. It contained not only an oath of allegiance to the Republic of Venice, but also spelled out the constitutional limitations to the Doge's power, which he swore to abide by.
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Promissione Ducale in the context of Signoria of Venice
The Signoria of Venice (Serenissima Signoria) was the supreme body of government of the Republic of Venice. The older Commune of Venice was replaced by the Signoria from 1423 on, being later officially adopted in the Promissione Ducale by Cristoforo Moro (12 May 1462). It constituted a center of power which included the doge's power.
The Signoria can be thought of as the combination of the Doge and the other persons commissioned to collaborate and to rule with him. With the passage of time these functionaries became copartners.
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