Treaty of Naples was a political-military agreement between the Kingdom of Spain and the Kingdom of Poland, signed in Naples in late 1639. The Polish king Władysław IV agreed to raise an army of 17,000 men, which would consist of 12,000 cavalry and 5,000 infantry. Following transit across the imperial territory, the troops were to be employed under Spanish command in Flanders against the French. The Spanish king Felipe IV, apart from covering recruitment and maintenance cost, was to pay the Polish monarch 500,000 Neapolitan escudos. The Poles almost immediately demanded re-negotiation of the treaty, which resulted in another agreement being concluded in 1641; the Spaniards were to pay more for an even smaller army. This treaty was not implemented either, and the Madrid court cancelled the deal in early 1642. The treaty remains the only bilateral Spanish-Polish military alliance agreement ever concluded between the two countries.
Spain and Poland until mid-1630s
Until the early modern period, relations between Spain and Poland were close to non-existent.quasi-political interactions were sporadic, e.g. princess Richeza in 1152 married Alfonso VII Politically the two countries operated in entirely different zones; the former focused on the Iberian Peninsula, western/central Mediterranean and northern slopes of the Pyrenees, the latter concentrated on the Baltic and huge plains in the Oder-Vistula-Dnieper basins.in the Middle Ages there were some 120 travellers from Poland who visited the Iberian Peninsula; in the 16th century the figure was around 90, and in the 17th century around 170, Emilia Dowgiało, O flamenco polskim piórem, Wrocław 2018, , s. 148. How many Spaniards visited Poland is not clear However, in the 16th century both states emerged as continental powers and their geographical interests became more closely aligned.Ryszard Skowron, Olivares, Wazowie i Bałtyk. Polska w polityce zagranicznej Hiszpanii w latach 1621–1632, Kraków 2002, , see esp. the chapter Geopolityczna przestrzeń spotkań, 1517–1598 The first major political encounter turned out to be a conflict; the crowns of Spain and Poland claimed the south-Italian heritage of Bona Sforza, the late queen-consort of Poland. In the late 16th century both courts started to maintain diplomatic representatives in each other's capitals,Ernest Kowalczyk, Making diplomacy through culture: Mikołaj Sękowski, the Polish envoy to Naples and Madrid in the late sixteenth century, [in:] The Journal for Renaissance and Early Modern Diplomatic Studies 3 (2019), p. 53 and politicians began to consider would-be opportunities related.see Skowron 2002, especially the chapter Hiszpańsko-polskie relacje dyplomatyczne w latach 1598–1623 First major attempts to achieve some synergy occurred in early phases of the Thirty Years' War. In the mid-1620s Felipe IV of Spain intended to crack down on Dutch merchant shipping on northern routes,Zbigniew Anusik, Olivares, Wazowie i Bałtyk [review], [in:] Przegląd Nauk Historycznych 4/1 (2005), p. 164 while Sigismund III of Poland, himself of Swedish origin, had his eyes set on regaining the throne in Stockholm. Diplomatic services of both monarchs worked to build a navy, possibly financed by the Spaniards and manned by the Poles, which would seize control over the western Baltic. However, interests of both kingdoms were not exactly the same; moreover, the emperor and his allies pursued their own goals.e.g. Felipe IV was ready to engage against Sweden only in case the emperor does, Anusik 2005, p. 165Wallenstein, Vasa Dynasty and Spanish-Polish Fleet in the Baltic Sea, 1628-1632. Karel Staněk, Michal Wanner. 2018 (in Spanish). The result was that a joint fleet was captured by the Swedes in 1631. In 1632 Spain withdrew from active Baltic policy, and the Polish–Lithuanian Commonwealth Navy was dismantled as well.Anusik 2005, pp. 158, 170
The new Polish king Władysław IV, crowned in 1632, resumed the plans harbored by his father. In 1634 he sent a special envoy to Madrid.he envoy was Wilhelm Forbes, Skowron 2002, pp. 39-40. Władysław IV was at the time well known in Spain and enjoyed sort of excellent media publicity. El sitio de Bredá (1625) by Calderón featured "Vladislao Sigismundo Principe de Polonia y Suecia"; in the drama he is lectured by Espínola and remains firm admirer of the Spanish monarchy Apart from usual negotiations on the Sforza heritage, the talks focused on compensation for the Polish fleet lost to the Swedes when nominally at the service of Felipe IV and ensuring Spanish posts and pension for two royal brothers.Skowron 2002, pp. 38-39 The main point, however, was Spanish financial support for future Polish military effort against Sweden, since 1630 the formal belligerent in the Thirty Years' War. The Polish-Swedish 1629 Altmark truce was to expire in 1635 and the Polish monarch was considering renewal of the conflict. In 1634 Władysław sent another envoy,the envoy was a religious, abbot of the Lubin Benedictine monastery Stanisław Mąkowski, Zbigniew Anusik, Marx i Pax [review], [in:] Przegląd Nauk Historycznych 14/2 (2015), p. 305 and in 1635 another one followed.the envoy was a young representative of one of the most powerful oligarchic families, Jerzy Sebastian Lubomirski Anusik 2015, p. 294 Until that time Madrid adopted an ambiguous stand; the Spaniards politely listened to Polish demands, but there were no tangible results. This changed in the spring of 1635, when two envoys were agreed to travel to Warsaw.they were Alonso Vázquez de Miranda and Jean de Croy, Ryszard Skowron, Mars i Pax. Polsko-hiszpańskie relacje polityczne w latach 1632–1648, Kraków 2013, , p. 58 However, they did not realize the urgency. French envoys, sent from Paris at approximately the same time but with opposite objectives, travelled by sea and arrived in Poland in May 1635 just in time to secure prolongation of the Altmark truce in Stuhmsdorf.Anusik 2015, p. 296 The Spaniards travelled by land and with many detours; they reached the king (who at the time acted as the Grand Duke of Lithuania) in Vilnius in August 1636.Anusik 2015, p. 301 It was there that they first proposed that an army be raised in Poland to join the fighting in ranks of the Catholic League.Anusik 2015, p. 297, Skowron 2013, p. 85. A number of soldiers recruited in Poland, most probably so-called lisowczycy, since October 1635 fought against the French in Flanders in ranks of the imperial army under the command of Matthias Gallas. This is probably when Rembrandt saw them. Their presence elicited from the French king Louis XIII a letter of protest, directed to the Polish king Władysław IV, Paweł Szadkowski, Los polacos en el ejército español en los siglos XVI y XVI, [w:] Enrique García Hernán (red.), Presencia polaca en la milicia española, Madrid 2020, ISBN 9788490914915, p. 65
Vasas, Habsburgs and the French (1637–1639)
The year of 1637 produced what seemed like an emerging alliance between the Habsburgs and the Polish Vasas. Madrid granted pension to two royal brothers and conferred upon prince John Casimir the Toisón d’Or order. Before leaving Warsaw the Spanish envoy Vázquez de Miranda has also agreed to pay compensation for the fleet lost in Wismar and interests on Sforza's heritage,Anusik 2015, pp. 301-302 though there was no tangible result when it comes to a job for the Polish prince;Miguel Conde Pazos, El tradado de Nápoles. El encierro del príncipe Juan Casimiro y la leva de Polacos de Medina de las Torres (1638–1642), [in:] Studia Histórica 33 (2011), p. 125 only vague concepts about his role in command of the Mediterranean fleet or an army in Flanders were floated.Miguel Conde Pazos, La monarquía católica y los confines orientales de la Cristianidad. Relaciones entre la case de Austria y los Vasa de Polonia [PhD thesis Universidad Autónoma de Madrid], Madrid 2016, p. 395 The major step, however, was related to the emperor. The Vienna Habsburgs and the Warsaw Vasas agreed on a so-called Family Pact. Władysław IV and the emperor Ferdinand III were cousins, as mother of the Polish king was sister to emperor Ferdinand II. However, in line with the pact they became also brothers-in-law, as Władysław IV was agreed to marry Cecilia Renata of Austria, the sister of Ferdinand III. Though the agreement sealed some heritage and succession issues and did not cover military co-operation, it seemed that following years of indecision, the king of Poland was firmly leaning towards Vienna instead of Paris.
In early 1638 prince John Casimir left Poland for Spain; it is not entirely clear whether Madrid and Warsaw had agreed on his future role on the Iberian Peninsula or whether he travelled to speed negotiations up. During his stay in Vienna the Paris press broke the news on his future appointment as viceroy of Portugal; Spanish sources suggest it was merely an option, considered at Consejo de Estado.Olivares thought it reasonable, given huge grain imports from Poland to Portugal. Margarita de Saboya was already to be replaced as virrey following so-called Revolta de Manuelinho, Conde Pazos 2016, p. 402. Other members of the council remained skeptical, Conde Pazos 2011, p. 127, Conde Pazos 2016, p. 401 However, in May the French detained the prince in Port-de-Bouc, as he was travelling from Italy to Spain along the Mediterranean coast.Conde Pazos 2011, p. 128 Officially he was charged with espionage,Conde Pazos 2016, p. 405 but scholars speculate that cardinal Richelieu seized the opportunity to dissuade Władysław IV from military alliance with the Habsburgs and from entering the Thirty Years' War.Conde Pazos 2016, pp. 405-406 During the summer it turned out that the royal brother would not be freed any time soon. In October 1638 Władysław met Ferdinand III in Nikolsburg to agree further action; both monarchs decided to seek mediation of Italian states, usually on good terms with the king of France. A Tuscan citizen in service of the Polish king, Francisco de Bivoni,“Bivoni” spelling adopted after Conde Pazos 2011. Elsewhere the same scholar adheres to the “Biboni”, see Conde Pazos 2016. Other scholars adhere to the “Bibboni” spelling, see e.g. Maciej Serwański, Francja wobec Polski w dobie wojny trzydziestoletniej, 1618–1648, Poznań 1986, . Bivoni was earlier engaged in talks with the French in Paris regarding liberation of Jan Kazimierz, Serwański 1986, p. 248 was sent to the Apennine Peninsula.Conde Pazos 2011, p. 129 In late 1638 he held talks in Republic of Venice and in early 1639 he was in Republic of Genoa, in both cases assisted by the Spanish diplomacy.Conde Pazos 2011, p. 129, Conde Pazos 2016, p.413 He was also empowered to represent the Polish king in the Duchy of Parma; he might have been there in the early spring of 1639., though sources do not confirm this, Conde Pazos 2016, p. 423 All these efforts proved fruitless; Richelieu did not change his stand and John Casimir remained in the French custody for already a year.
Madrid and Warsaw decide to enter military talks (1639)