On the 15th of August, 1581, the Contrada dell'Aquila organized a Palio to which the other Contrade participated for the first time. The year 1597 seemed to be the year of the first Palio "alla tonda", that is run around the Piazza del Campo.

In 1650, the last "Bufalata" was run and the Palio "alla tonda", very different from the "alla lunga" races of the aristocrats, became the main competition of the Contrade.
In 1689, the Palio was repeated for the second time by the Contrada dell'Istrice that organized a race on the same day to celebrate its victory.
The Palio dell' Assunta was born a little later. It took place on the 16th of August instead of the 15th, the traditional day of the Palio "alla lunga".
Only in the year 1699, instead, the first "tratta" by lot of the horses was instituted, and in 1720, after some serious accidents, it was established that only ten Contrade at a time could compete. Until 1727, there were numerous acknowledged Contrade, but only ten of them could participate in the Palio.
Two years later, a Commission presented the report that inspired the announcement on the "Nuova divisione dei confine tra le Contrade" that was strongly backed by Violante Beatrice of Bavaria, governor of the city. Thanks to it, the number of Contrade with definite borders and the same number of inhabitants raised to seventeen. This announcement exists still today and it has never been either abolished or modified.
In the XIX century, the history of the Palio was enriched with new characteristics, in line with the process of unification of Italy that took place in the second half of the century. In 1848, the Sienese already supported the Unification of Italy. The Contrade were already consolidated institutionally and politically and they founded friendly societies that soon engaged in the events outside the city. Therefore, on the occasion of the wars of independence in 1848, in 1859 and in 1866, the Palio was suspended and the Contrade raised money and provisions for the soldiers.
Or, in 1893, they organized some protests to avoid the closing up of the Università degli Studi. The Palio was also sensitive to the two world wars, during which it was further suspended. Yet, after the war conflicts, extraordinary "Palii" celebrated their end.