A brisk monograph treating John Churchill’s (later Duke of Marlborough) daring 1704 German campaign, culminating in the defeat of Louis XIV and Marshal Tallard at Blenheim, effectively ending French designs on the Holy Roman Empire for most of the 18th century. The predatory Louis, unbeaten for 40 years, had unwittingly forged William of Orange’s Grand Alliance by promising James II restoration to the English crown. Yet the Dutch primarily wanted security, the British parliament seethed of the Glorious Revolution’s partisan aftermath, and imperial commander Prince Lewis of Baden was innately conservative. Escaping capture in 1702, Marlborough, seen as the scheming son of a penurious royalist, and his great ally Eugene of Savoy, another aggrieved aristocrat, seized on Count Wratislaw’s suggestion to relieve Vienna by marching up the Danube. Well financed, the Allies paid for supplies while campaigning, the French relied on confiscation; but Marlborough terrorized the Bavarian countryside to punish Maximillian Emmanuel. The allies won at Schellenberg in July, placing themselves between the French and Vienna. In the August battle, Spencer asserts Tallard ought to have defended the Nebel river with cavalry as Marlborough’s infantry sought to gain a foothold. Yet the French horse almost simultaneously lost a skirmish, shockingly and in view of the garrisoned town, just before the main battle. For this reason, the author asserts Tallard should not have given battle but retreated. In the successful assault, fought over 3 fronts, the Allies suffered 12,500 casualties including 300 of the 700 British officers; the French lost all but 250 of 4,500 officers and some 40,000 troops. The shock of the result was French surrender and the capture of Tallard. Bavaria was knocked from the war, which despite the French being driven from the Low Countries after Ramillies in 1706, persisted until 1714. Spencer asks why Blenheim isn’t remembered with same warmth of Agincourt, answering that partisan opposition to Marlborough’s character, as well as that of Swift and Macaulay, has diminished the affair. Accessible and well illustrated.