During the Renaissance, the papacy was not only a spiritual authority but also a political and military power. No one embodied this better than Giuliano Della Rovere, better known as Pope Julius II.

Before becoming pope, Della Rovere built his power as a cardinal, appointed by his uncle, Sixtus IV. He acquired fiefdoms in Umbria and the Marches. He was caught up in the tensions of the time and, as an opponent of the Borgias, was forced into exile in France during the pontificate of Alexander VI (Rodrigo Borgia). After Alexander's death in 1503, Giuliano Della Rovere was elected pope, taking the name Julius II. He aimed to strengthen the Papal States and restore their prestige and control. Unlike many predecessors, Julius II donned armour and led military campaigns personally. He became known as the "warrior pope," determined to reconquer rebellious cities, weaken rival families, and limit the power of foreign forces in Italy.

One of his first goals was to restore cities like Bologna and Perugia to Roman rule. In 1506, he personally led the siege of Bologna, held by the Bentivoglio family, returning it to papal control. In 1508, he joined the League of Cambrai, an alliance of France, the Empire, and Spain, formed to oppose Venetian expansion in northern Italy and the Adriatic coast of Romagna. King Louis XII’s forces badly defeated Venice at Agnadello. Fearing French dominance, Julius II then promoted the Holy League, uniting Spain, the Empire, England, Venice, and Rome to expel the French from Milan. Although the French won at Ravenna (1512), they suffered major losses and soon evacuated Italy. Beyond these diplomatic manoeuvres, Julius II remained focused on preventing any one power from dominating Italy, which would mean losing the Papal States' independence.

Yet Julius II was not only a warrior, but also a pope of great works. Alongside his military and political campaigns, he commissioned Michelangelo Buonarroti for the Sistine Chapel and began the reconstruction of St. Peter's Basilica. He died in 1513, leaving a stronger papacy, but also an Italy more unstable and challenged than the great European powers.