They, together with several associates, known as the Forty Conspirators, killed the Secretary of State, Miguel de Vasconcelos, and imprisoned the king's cousin, Margaret of Savoy, who had been governing Portugal in his name.

He also organized the army, re-established the 'Military Laws of King Sebastian',[9] and undertook a diplomatic campaign focused on restoring good relations with England.

Louis was at war with Spain at that time; he had to control rebellions within France that were supported and financed by Madrid and had to send French armies to fight the Spanish Habsburgs on three different fronts.

It lasted eighteen years before Richelieu's successor as unofficial foreign minister, Cardinal Mazarin, broke the treaty and abandoned his Portuguese and Catalan allies to sign a separate peace with Madrid.

Seven years later, in the late stages of the Portuguese Restoration War, relations between the two countries thawed to the extent that the young (but sickly) Afonso VI of Portugal married a French princess, Marie Françoise of Nemours.

The strained relations persisted during the short-lived Commonwealth period, when the republican government that had deposed Charles I ruled England and then Ireland and Scotland.

After the restoration of the Stuart dynasty, it became possible for Portugal to compensate for the lack of French support by renewing its alliance with England,[12] with experienced soldiers and officers available from the demobilised New Model Army.

That took the form of a dynastic marriage in 1662 between Charles II and Afonso VI's sister, Catherine of Braganza, which assured Portugal of outside support in its conflict with Spain.

The English alliance helped peace with Spain, which had been drained by the Thirty Years' War and had no stomach for further warfare with other European powers, especially a resurgent England.

Three theaters of warfare were eventually opened, but most activity focused on the northern front, near Galicia, and on the central frontier between Portuguese Alentejo and Spanish Extremadura.

Campaigns typically consisted of correrias (cavalry raids) to burn fields, sack towns, and steal large herds of enemy cattle and sheep.

For long periods, without men or money, neither side mounted formal campaigns, and when actions were taken, they were often driven as much by political considerations, such as Portugal's need to impress potential allies, as by clear military objectives.

Since there was often no money to pay or support the troops (or to reward their commanders), the Spanish crown turned a blind eye to the smuggling, contraband, profiteering, disorder, and destruction that had become rampant on the frontier.

Despite these domestic problems, the expulsion of the Dutch from Brazil (1654) and the signing of a treaty with England (also in 1654) improved Portugal's diplomatic and financial position temporarily and gave it needed protection against a naval raid on Lisbon.

Nonetheless, the overriding goal, a formal pact with France, continued to evade Portugal, whose weakness and isolation had been driven home by its virtual exclusion at the negotiations for the European settlement-of-settlements, the new realpolitik of the Peace of Westphalia (1648).

With this treaty and the end of hostilities in Catalonia in 1652, Spain was again ready to direct its efforts against Portugal, but it faced a lack of men, resources, and, especially, good military commanders.

[16] During the second stage, the war became a frontier confrontation characterized by attrition, often featuring local forces composed of familiar neighbors, yet this intimacy failed to temper the brutality exhibited by both sides.

In April 1663, John of Austria the Younger, Philip IV's illegitimate son, invaded Alentejo, commanding an army of 20,000 provisioned for six weeks.

They were led by the German soldier of fortune, Friedrich Hermann von Schönberg, Count of Mértola, The brigade, under Schomberg's leadership, proved a decisive factor in winning back Portugal's independence.

[20] They defeated the Spanish in a major engagement at Ameixial on 8 June 1663, and this forced John of Austria to abandon Évora and retreat across the border with heavy losses.

[24] Luís de Meneses, the Count of Ericeira, economic adviser to the prince regent, advocated the development of a native textile industry based on a Flemish model.

Factories were established at Covilhã, in an area of central Portugal where there was easy access to flocks of sheep and clean mountain water, but they were highly unpopular with both local consumers and traditional weavers.

More importantly, after 1668, Portugal increasingly cultivated intellectual ties with Western Europe, especially France and England, marking a shift away from its Iberian roots and towards cultural and political independence from Spain.