A French army besieged the Spanish-held town of Arras, capital of the province of Artois, then part of the Spanish Netherlands, which surrendered after holding out for 48 days.

In 1938, historian CV Wedgwood argued the Thirty Years War (1618-48) and the Dutch Revolt (1568-1648) formed part of a wider, ongoing European struggle, with the Habsburg-Bourbon conflict at its centre.

This interpretation is generally accepted by modern historians, and makes the Franco-Spanish War a connected conflict; this wider perspective helps in understanding strategic objectives.

[3] When Spain restarted its war of reconquest against the Dutch in 1621 at the end of the Twelve Years' Truce, it initially won a series of victories, but by 1633 found itself on the retreat again.

[5] Concerned by the prospect of the Habsburgs making peace on favourable terms in both the Empire and the Netherlands, Louis XIII and his chief minister Richelieu decided on direct intervention.

[7] Arras was strongly held, and its fortifications recently updated, but its most formidable defences were the four waterways running around the town, making it hard for besiegers to blockade it, while complicating their communications and logistics.

Many Spanish officials also felt it was time to accept Dutch independence, but despite these challenges, Spain supported by the Austrian Habsburgs remained a formidable power.