Prof. Dr. jur. Hermann Louis Brill (February 9 1895 - June 22 1959) was a German politician (SPD).

Brill was born in the small town of Gräfenroda, Thuringia on February 9 1895 as the son of a tailor; after finishing school, he attended the Herzog-Ernst-Seminar in Gotha to become a teacher. His political career began in 1918, when he entered the USPD; less than two years later, he became a member of the Thuringian parliament (Landtag) for the first time, which he stayed until 1933.

However, Brill only stayed a member of the USPD for four years; in 1922, he left the party again and found his new political home in the SPD instead. In 1932, Brill was also a member of the federal German parliament (Reichstag).

The Nazis were met with resistance from Brill ever since he first got in contact with them after they became part of the reigning coalition in Thuringia in 1930; Brill was especially opposed to the politics of national socialist minister of the interior Wilhelm Frick, and led a committee of investigation established by the Landtag in 1932 that scrutinised Frick's practices. It was also during this time that he met Adolf Hitler, who appeared as a witness in front of the committee, in person, an experience that led to him taking the decision to resist Hitler "at any time, everywhere and under all circumstances" ("jederzeit, überall, unter allen Umständen").

Following Hitler's rise to power, Brill left the SPD in May 1933, scandalised by the party executive's passive attitude towards Hitler; one year later, he founded the Deutsche Volksfront, a resistance group, in Berlin together with Otto Brass. Brill also wrote a number of essays and flyers during this time; he was arrested several times by the Gestapo, and finally sentenced to 12 years in jail in 1938 for high treason, after the workings of the Deutsche Volksfront had been discovered.

After first being jailed in the Zuchthaus Brandenburg-Görden, he was brought to the Konzentrationslager Buchenwald in 1943; following the liberation of the inmates of Buchenwald on April 11 1945, he wrote the "Buchenwalder Manifest der demokratischen Sozialisten" ("Buchenwald Manifest of the Democratic Socialists").

The same month, Brill also began creating a plan for the administrative rebuilding of Thuringia for the American administration. In June 1945, he was appointed Regierungspräsident (president of the government) of Thuringia, an office he lost again in July after Thuringia became part of the Soviet zone of occupation, due to pressure from Walter Ulbricht; in May 1945, he founded the Bund demokratischer Sozialisten (Federation of Democratic Socialists) in Thuringia, which finally evolved into Thuringia's SPD branch, with Brill as the first chairman, but after being arrested and interrogated twice by the Soviet administration, he finally left Thuringia at the end of 1945 and began working for the American administration in Berlin.

In 1948, Brill helped draft a constitution (Grundgesetz) for the new German republic, and from 1949 to 1953, he was a member of the first Bundestag, the parliament of the newly-founded Germany; in his last year as a member of parliament, he put through the first Bundesentschädigungsgesetz (compensation law) for those who had been subjected to prosecution based on political views, race or religion.

In later years, Brill taught at the universities of Frankfurt and Speyer; he was responsible for the introduction of political science as a field of study in Germany, and wrote several articles pertaining to issues such as the German reunification.

Hermann Brill died on June 22 1959 in Wiesbaden.