Butler, Count Walter (d. 1634), imperial governor and soldier, was born in Ballinakill, near Roscrea, Co. Tipperary, second son of Peter Butler and Catharine Butler (née de Burgo). The family originated in Paulstown, Co. Kilkenny, and were a cadet branch of the house of Ormond. Walter may have fought on the imperial side at the battle of the White Mountain, near Prague (8 November 1620), but is first mentioned in the early 1630s as lieutenant-colonel of the regiment of his cousin James Butler. He distinguished himself at the siege of Frankfurt an der Oder in April 1631 where, according to his regimental chaplain Thomas Carew (qv), he bravely resisted the onslaught of Swedish troops until wounded and taken prisoner. Although he received a testimonial of valour from King Gustavus Adolphus of Sweden, some on his own side accused him of treachery. He was imprisoned for six months until he purchased his freedom and joined Tiefenbach's imperial army in Silesia. He travelled twice to Poland to raise troops and in January 1632 he was entrusted by Albrecht von Wallenstein (who had just resumed command of the imperial armies) with the defence of his own duchy of Sagan, and given command of his cousin's regiment of dragoons. For his heroism against the Saxons, Butler was assigned winter quarters in the Silesian county of Jägerndorf, where he married Countess Anna Maria von Dohna (a protestant converted to catholicism soon after their marriage). He was military governor of Meissen and, always willing to help his fellow countrymen, was a generous patron to the Irish Franciscan monastery at Prague.
Little is known of his activities until 12 January 1634, when he was one of the forty-nine commanders who signed the first declaration of Pilsen, pledging their support to Wallenstein. Emperor Ferdinand II, frightened of Wallenstein's ambitions and believing him to be intriguing against him, issued a secret decree (24 January 1634) deposing him as imperial commander, granting amnesty to the signatories of Pilsen, and ordering his arrest or death. In February 1634 Butler, then in winter quarters at Klatrub, received orders from Wallenstein to bring his regiment of dragoons to Prague, where the duke hoped to negotiate with the emperor. On the way he met Wallenstein on 23 February and the two took quarters in the town of Eger (Cheb) in western Bohemia. Wallenstein (probably seriously ill at this stage) told Butler of his grievances against the emperor, and offered him generous rewards for his support, including the command of two well-paid regiments. Although Butler declared his willingness to serve Wallenstein, he was aware that imperial favour could be gained by killing him. He sent a message to an imperial agent that he was loyal to the emperor and was only following Wallenstein under coercion. He conspired with Lt.-col. John Gordon and Maj. Walter Leslie, two Scottish officers in the Eger garrison, to infiltrate a hundred of his men into the town on 25 February 1634; seventy guarded the approaches to the castle while thirty were hidden within the castle. That evening a banquet was held at the castle and, when the signal was given, Butler, Gordon, and Leslie leapt to their feet with a cry of ‘Vivat Ferdinandus’ and cut down Wallenstein's followers, Ilow, Terzka, Kinsky, and Neumann. Butler and two of his officers, Maj. Robert Geraldine and Lt.-col. Walter Devereux, then burst into Wallenstein's quarters at the burgomaster's house in the town square. Wallenstein was roused from his sleep and Devereux ran him though the chest with his halberd. Butler and Gordon then issued a proclamation declaring Wallenstein's treason, and made the town burghers and troops encamped around the town swear fidelity to the emperor.
Since Wallenstein had already been deserted by most of his troops he may not have posed a serious threat to the imperial cause, but Ferdinand was none the less delighted to be rid of him, all the more so as it appeared that Butler had acted on his own initiative. Butler appeared at the imperial court shortly afterwards to claim his reward: he was ennobled as an imperial count, appointed lord chamberlain, and endowed with the estate of Friedberg, Bavaria, one of the largest of Wallenstein's domains. According to an Irish Franciscan, Butler's assassination of Wallenstein ‘was absolutely necessary for the welfare of the house of Austria and the whole catholic church, and more praiseworthy than can ever be described. It has made our county and nation, otherwise quite unheard of here, most famous and well known’ (Jennings, 216).
Butler fought at the battle of Nördlingen (7 September 1634) and after the imperial victory took the towns of Aurach and Schorndorf in Württemberg. He died at Schorndorf 25 December 1634, having entrusted his remains to the keeping of the Irish Franciscan monastery at Prague, to which he left 30,000 florins; he also gave bequests to other religious orders and to Walter Devereux (d. 1639). Since his only child (a girl) died in infancy, his estate of Friedberg was claimed by his grand-nephew Thomas Butler of Clonmore. His family, Butler zu Pardany und Erdötelek, still survives in Bavaria.
Butler was immortalised as an Iago-like character in Friedrich Schiller's great dramatic trilogy Wallenstein (1800), translated into English by S. T. Coleridge.