Maximilian, Margrave of Baden (Maximilian Alexander Friedrich Wilhelm; 10 July 1867 – 6 November 1929), also known as Max von Baden, was a German prince, general, and politician. He was heir presumptive to the throne of the Grand Duchy of Baden, and in October and November 1918 briefly served as the last chancellor of the German Empire and minister-president of Prussia. He sued for peace on Germany's behalf at the end of World War I based on U.S. President Woodrow Wilson's Fourteen Points and took steps towards transforming the government into a parliamentary system. As the German Revolution of 1918–1919 spread, he handed over the office of chancellor to SPD Chairman Friedrich Ebert and unilaterally proclaimed the abdication of Emperor Wilhelm II. Both events took place on 9 November 1918, marking the beginning of the Weimar Republic.

Born in Baden-Baden on 10 July 1867, Maximilian was a member of the House of Baden, the son of Prince Wilhelm Max (1829–1897), third son of Grand Duke Leopold (1790–1852) and Princess Maria Maximilianovna of Leuchtenberg (1841–1914), a granddaughter of Eugène de Beauharnais. He was named after his maternal grandfather, Maximilian de Beauharnais, and bore a resemblance to his cousin, Emperor Napoleon III.

Max received a humanistic education at a Gymnasium secondary school and studied law and cameralism at the Leipzig University. Upon the order of Queen Victoria, Prince Max was brought to Darmstadt in the Grand Duchy of Hesse and by Rhine as a suitor for Victoria's granddaughter, Alix of Hesse-Darmstadt. Alix was the daughter of Victoria's late daughter, Princess Alice, and Louis IV, Grand Duke of Hesse. Alix quickly rejected Prince Max, as she was in love with Nicholas II, the future Tsar of Russia. Max von Baden was homosexual and even listed on an according list of the Berlin criminal police as a young officer, however in 1900 he decided for dynastic reasons to marry Princess Marie Louise of Hanover and Cumberland. So did the future King Gustaf V of Sweden who married Max's cousin Victoria of Baden.

After finishing his studies, he trained as an officer of the Prussian Army. Following the death of his uncle Grand Duke Frederick I of Baden in 1907, he became heir to the grand-ducal throne of his cousin Frederick II, whose marriage remained childless. He also became president of the Erste Badische Kammer (the upper house of the parliament of Baden). In 1911, Max applied for a military discharge with the rank of a Generalmajor (Major general).

Upon the outbreak of World War I in 1914, he served as a general staff officer at the XIV Corps of the German Army as the representative of the Grand Duke (XIV Corps included the troops from Baden). Shortly afterwards, however, he retired from his position (General der Kavallerie à la suite) as he was dissatisfied with his role in the military and was suffering from ill health.

In October 1914, he became honorary president of the Baden section of the German Red Cross, thus beginning his work for prisoners-of-war inside and outside Germany in which he made use of his family connections to the Russian and Swedish courts as well as his connections to Switzerland. In 1916, he became honorary president of the German-American support union for prisoners of war within the YMCA world alliance.

Due to his liberal stance he came into conflict with the policies of the Oberste Heeresleitung (OHL – Supreme Army Command) supreme command under Paul von Hindenburg and Erich Ludendorff. He openly spoke against the resumption of the unrestricted submarine warfare in 1917, which provoked the declaration of war by the United States Congress on 6 April.

His activity in the interests of prisoners of war, as well as his tolerant, easy-going character gave him a reputation as an urbane personality who kept his distance from the extremes of nationalism and official war enthusiasm in evidence elsewhere at the time. Since he was almost unknown to the public, it was mainly due to Kurt Hahn, who served from spring 1917 in the military office of the Foreign Ministry, that he was later considered for the position of chancellor. Hahn maintained close links with Secretary of State Wilhelm Solf and several Reichstag deputies like Eduard David (SPD) and Conrad Haußmann (FVP). David pushed for Max to be appointed Chancellor in July 1917, after the fall of Chancellor Bethmann Hollweg. Max then put himself forward for the position in early September 1918, pointing out his links to the social democrats, but Emperor Wilhelm II turned him down.