victory. Once again, Richelieu used French financial power to bridge differences between the Swedes and the German princes; the 1631 Treaty of Bärwalde provided funds for the Swedes and their Protestant allies, including Saxony and Brandenburg. These amounted to 400,000 Reichstaler per year, or one million livres, plus an additional 120,000 for 1630. While the payments were less than 2% of total French income, they boosted that of Sweden by more than 25%, and allowed Gustavus to support an army of 36,000. Gustavus used this army to win victories at Breitenfeld in September 1631, then Rain in April 1632, where Tilly was killed. Ferdinand turned once again to Wallenstein, who realised Gustavus was overextended and established himself at Fürth, from where he could threaten his supply lines. The largest battle of the war took place in late August, when an assault on the Imperial camp outside the town was bloodily repulsed, arguably the greatest blunder committed by Gustavus during his German campaign. Two months later, the Swedes and Imperials met at Lützen, where both sides suffered heavy casualties; Gustavus himself was killed, while some Swedish units incurred losses of over 60%. Fighting continued until dusk when Wallenstein retreated, abandoning his artillery and wounded. Despite their losses, this allowed the Swedes to claim victory, although the result continues to be disputed. Following the death of Gustavus, Swedish policy was directed by his extremely capable Chancellor Axel Oxenstierna; in April 1633, the Swedes and their German allies formed the Heilbronn League with funding provided by the French and in July their combined forces defeated an Imperial army led by the Bavarian general Bronckhorst-Gronsfeld at Oldendorf. Wallenstein's reputation had been severely damaged by Lützen, while critics claimed he had failed to adequately support the Bavarians. Combined with rumours he was preparing to switch sides, Emperor Ferdinand ordered his arrest in February 1634; on 25th, he was assassinated by his own officers in Cheb. The loss of Wallenstein and his organisation left Emperor Ferdinand reliant on Spain for military support, whose main concern was to re-open the Spanish Road for their campaign against the Dutch. This meant the focus of the war now shifted to the Rhineland and Bavaria. Cardinal-Infante Ferdinand of Austria, newly appointed Governor of the Spanish Netherlands, raised an army of 18,000 in Italy, which met up with an Imperial force of 15,000 at Donauwörth on 2 September 1634. Three days