Louis William served first under Raimondo Montecuccoli against Turenne, and then under the duke of Lorraine. At the siege of Vienna by the Turks, in 1683, he threw his forces into the city, and by a brilliant sally effected a junction with Jan III Sobieski and the Duke of Lorraine, who had come to its relief. In 1689 he defeated the Turks at Niš. Louis came to be called the Türkenlouis or shield of the empire. The Turks called him the red king, because his red uniform jacket made him very visible on the battlefield. He was known as a defender of Europe against the Turks, as was Eugene of Savoy. As a military commander in the service of the Holy Roman Empire, in 1689 he was made chief commander of the Imperial army in Hungary, where he scored a resounding victory against the Ottomans at Slankamen in 1691. Louis saw Osijek as a location of exceptional strategic importance in the war against the Ottomans. He urged the repair of the city walls, and proposed construction of a new fort called Tvrđa, according to Vauban's principles of military engineering. Shortly afterward he was sent to head the army of the Rhine in the War of the Grand Alliance. In 1701, he built the Bühl-Stollhofen Line, a line of defensive earthworks designed to protect northern Baden from French attack. He later led the imperial army in the War of the Spanish Succession where he successfully concluded the Siege of Landauin September 1702, but soon had to withdraw across the Rhine and was defeated by the French under the Duke of Villars at Friedlingen. In 1704 however, he participated in the successful German campaign of Marlborough and Eugene of Savoy. He distinguished himself in the Battle of Schellenberg and besieged and conquered Ingolstadt and Landau, thus drawing Bavarian troops away from the decisive Battle of Blenheim. He died in at his unfinished Schloss Rastatt in 1707. His wife took up a regency for their son, Louis George. The latter took over the government from his mother in October 1727.
Marriage and children
The Emperor gave him a young heiress to wed, Sibylle of Saxe-Lauenburg. They had the following children:
Augustus George Simpert of Baden-Baden, Margrave of Baden-Baden, married Marie Victoire d'Arenberg, no male issue;
Seventeen years after the margrave's death, the only one of his daughters to survive childhood, Princess Auguste, married Louis d'Orléans, son of the infamous French Regent and, at the time of the wedding, first in the line of succession to the throne of France. His descendant through this marriage became King Louis Philippe of the French in 1830. After the death of Louis, his widow built Schloss Favorite castle as a summer residence in memory of her husband. He was buried at the Stiftskirche in Baden-Baden.