In the 16th century, France, facing pressure from the Holy Roman Empire as well as the devastating effects of internal turmoil and religious wars, fended off these threats with support from the Ottoman Empire. Throughout the 16th century, the Ottoman navy aided France, ensuring the continued existence of their state. The Ottomans strengthened France against the Habsburgs by sending soldiers, providing financial assistance, or through commercial relations.
During this period, France found a new lease of life as the Ottomans engaged in conflict with the Habsburgs. Indeed, in 1532, King Francis I of France told the Venetian ambassador that he felt "secure against Emperor Charles V thanks to the Ottomans." In 1533, Suleiman the Magnificent sent 100,000 gold coins to the French King to ally with England and the German princes against Charles V. Commercial concessions, or capitulations, granted in 1569 further strengthened France economically.
Despite relying on Ottoman support to survive, France consistently denied its alliance with the Turks due to accusations of collaborating with infidels in Europe. It claimed it would participate in the Crusades when called upon, but stalled its counterparts, never joining any coalition against the Turks. While French ambassadors congratulated the sultans on Ottoman victories against Christians, the French government told its European counterparts that they had tried hard but failed to dissuade the Ottomans from taking Christian lands.
However, the relationship between the two states was so overt that French denials could not conceal the alliance. The Habsburgs accused the French of collaborating with the "enemy of Christianity." Emperor Charles V and the Pope even accused France of cooperating with infidels and threatened to organize a Crusade against the French King.
The relationship between the two states continued through permanent ambassadors in Istanbul and extraordinary envoys sent occasionally. French kings sent letters to their ambassadors in Istanbul and the Ottoman sultan. However, due to the possibility of letters being intercepted, the political alliance was generally maintained through the verbal statements of dispatched envoys. The ambassadors and messengers sent by the French government to Istanbul incited the Ottoman administration to send fleets and armies against the Holy Roman Empire. Messengers from France also provided the Ottoman administration with all kinds of news regarding the situation in Europe. The Ottoman sultans, in turn, sent troops against the Habsburgs to aid France whenever they saw it serving their own state's interests.
King Charles IX of France had sought support from the Ottoman ruler Selim II in 1572 to have his brother Henri elected to the vacant throne of Poland-Lithuania.
In a letter sent to the French ambassador in Istanbul on Nov. 30, 1572, the French King wrote: "Considering the Sultan one of my most reliable friends, I would be pleased if he were to make me feel the fruits of his friendship in this matter; for it is a matter I hold in high esteem and for which I shall remain grateful to him. I ask you to demonstrate all your skill and create a masterpiece of your craft by trying to persuade the Sultan to send an official delegation to Poland to urge the country's nobles to elect my brother and to demand that he be given precedence everywhere; should they choose someone else, let this message show them that they will forever be the Sultan's enemies. I believe my brother will thus be elected without any difficulty, and the emperor will be excluded from this election when the King of Poland is appointed."
The Habsburgs' threat against the French kings, especially after 1525, marked a significant turning point in the beginning of Ottoman-French relations and in relations between the Ottoman-French states and Western Europe. An alliance was formed between France and the Ottoman Empire throughout the 16th century and in the first half of the 17th century. However, the alliance was more of a benevolence from the Ottoman rulers toward France rather than a bilateral partnership. The most ironic aspect is that France, which survived thanks to Ottoman support, would, from the mid-17th century onward, seize any opportunity to support alliances against the Ottomans.