How did Francis I regain his sons after the Treaty of Cambrai?

Under the terms of the Treaty of Cambrai, signed in 1529, Francis I secured the release of his two eldest sons, who had been held as hostages by Charles V since the failed Treaty of Madrid.12

To regain his children, Francis I was required to fulfill several conditions:
* Financial Payment: He agreed to pay a ransom of 2,000,000 gold crowns to the Emperor.12
* Political Concessions: He formally renounced his claims in Italy and his rights as overlord in Flanders and Artois.1
* Abandonment of Allies: He agreed to abandon his existing political alliances.12

The ransom was collected with difficulty due to the depleted state of the French treasury, but the payment was ultimately successful. Following the agreement, the princes were released and were able to attend their father’s political marriage to Eleonora of Austria in 1530.2