Louis Hector Berlioz (December 11, 1803 – March 8, 1869) was a French Romantic composer, best known for his compositions Symphonie fantastique and Grande Messe des morts (Requiem). Berlioz made significant contributions to the modern orchestra with his Treatise on Instrumentation. He specified huge orchestral forces for some of his works; as a conductor, he performed several concerts with more than 1,000 musicians. He also composed around 50 songs for voice and guitar.
Berlioz was born in France at La Côte-Saint-André in the département of Isère, near Lyon. His father, a respected provincial physician and scholar, was responsible for much of the young Berlioz's education. His father was an atheist, with a liberal outlook; his mother was an orthodox Roman Catholic. He had five siblings in all, three of whom did not survive to adulthood. The other two, Nanci and Adèle, remained close to Berlioz throughout his life.
Unlike many other composers of the time, Berlioz was not a child prodigy; he began studying music at age 12, when he began writing small compositions and arrangements. As a result of his father's discouragement, he never learned to play the piano, a peculiarity he later described as both beneficial and detrimental. He became proficient at guitar and flute. He learned harmony by textbooks alone—he was not formally trained. The majority of his early compositions were romances and chamber pieces.