Sorry for my late response to Billy and yourself but Thursday and Friday saw me at Warwick Castle and then at Thorpe Park where a soaking cost me £20 for a cheapo tea shirt.Wellington was always seen as a defensive General but Assaye, Salamanca and Vitoria showed different. Salamanca was a lesson in opportunism.
I cannot speak for Assaye, however, Wellington was certainly a defensive General but in many cases during his time in Portugal and Spain the circumstances demanded it. While the British Army at it's height was about 250,000 there was nothing like that number for Wellington to call upon whereas the French had something like 310,000 spread across the country under Marshals Suchet, Marmont and Soult. Wellington was constantly worried that harassing one Marshal could have them borrow a division or two from another and so make life difficult.
Leading up to Salamanca, Wellington heard that Marmont's army although widely dispersed was larger than his but once again were so short of rations that the Marshal dare not concentrate his divisions too closely until he was certain where Wellington would strike. Marmont then made the mistake that cost him the battle when he mistook the cloud of dust from the Duke's supply wagons for a British retreat and sent three divisions spread out across Wellington's front. On seeing this the Duke who was eating a chicken leg, threw it over his shoulder and turned to his Spanish liaison officer remarked, "Mon cher Alava, Marmont est perdu."
Vitoria was not a particularly large or bloody Battle. The French lost 8,000 men , the allies 5,000. However, the effects of the battle was felt far beyond Spain as Austria immediately declared war on France. A Count Nugent took a copy of Wellington's dispatched to the Austrian Emperor who sent a message to Wellington offering him command of his armies.
Beethoven had been an ardent admirer of Bonaparte to the extent of dedicating his Symphony No 3 (Eroica) to him. However, on making himself Emperor of France the dedication was scribbled out. As for Vitoria, Beethoven wrote, Wellington's Victory, O91 which contains some themes you may recognise
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