The Siege of Breda of 1624-25 was a siege of the dutch city Breda of the Spanish army under Ambrogio Spinola in 1625 as part of the thirty years war.

Under Spinola's orders, the Spanish laid siege to Breda in August 1624, contrary to the wishes of their King. The city was heavily fortified and defended by a garrison of 7,000. Spinola rapidly invested its defences and hurled back a Dutch relief army under Maurice of Nassau attempting to cut his supplies. The defenders held. In February 1625, a second relief force, consisting of 7,000 Englishmen under Horace Vere and Ernst von Mansfeld, was also driven off. When Justin of Nassau surrendered Breda in June 1625 after a costly eleven-month siege, only 3,500 Dutchmen and fewer than 600 Englishmen had survived.

The Siege of Breda was Spinola's greatest success and one of Spain's last major victories in the Eighty Years' War. It was part of a plan to isolate the Republic from its Hinterland.

Spain's efforts in the Netherlands continued thereafter though political infighting hindered Spinola's freedom of movement. Yet the siege of 1625 captured the attention of the princes of Europe and, for a while longer, Spanish armies recaptured the formidable reputation they had held in the previous century.

In 1629, however, after Piet Heyn's capture of the Treasure fleet, Stadtholder Frederick Henry was able to capture the fortress city of 's-Hertogenbosch, breaking the land blockade. In 1637 Breda was recaptured by Frederick Henry after a four-month siege, and in 1648 it was finally ceded to the Dutch Republic by the Treaty of Westphalia.

The years after the Twelve Years' Truce among the darkest in the history of the Republic of the Seven United Netherlands. The economy of the Republic was under heavy pressure by Spanish blockades of the rivers de Waal, Meuse, Rhine, Scheldt and Ems. The increased activity of the Dunkirk pirates, attacks on the herring fleet, Spanish attacks in the West Indies and the decline in trade with the Iberian Peninsula, the Levant and the Baltic region contributed to the economic downturn. Spain had the rod in the Republic of Flanders to Lingen and the defensive to preserve the States' army had to be reinforced by 30,000 men to 48,000 men. That took a lot of money so that taxes had to be raised.

Moreover, the Republic became diplomatically isolated. France and England, which the Republic had made an alliance with in 1596, made peace with Spain and the payments from those countries stopped. In addition, continued payments to the Dutch Protestant armies in the Holy Roman Empire during the Thirty Years' War continue to prevent the armies of the Catholic League at the land borders were.

There were several motives for Breda siege. Spanish Brabant would be better protected when Breda would be conquered, because the strong from the Dutch border town regularly raids were in Spanish Brabant. In addition, neighbouring towns in Bergen op Zoom Republic's hands as the Spaniards easier to conquer with a foothold as Breda.

Another important reason was dented prestige of the Spanish army. In 1590, Breda was the list with the peat boat captured from Spain where the Spanish army, consisting of Spaniards but also Italians, did not behave heroically, despite their numerical superiority, they were surprised by the States after the soldiers to flee ignominiously beaten. This would disgrace with the conquest of a well-defended city of Breda be obliterated. And Spinola himself felt the failure of the Siege of Bergen op Zoom in 1622 as a blot on his escutcheon.

Spain also wanted to stand strong in negotiations over a possible peace. A conquest of Breda Spain would be tough with questions about religious freedom for Catholics in the Republic and the lifting of the blockade of the Scheldt.