Robert Schumann was a German composer and influential music critic. He is widely regarded as one of the greatest composers of the Romantic era. Schumann left the study of law, intending to pursue a career as a virtuoso pianist. He had been assured by his teacher Friedrich Wieck that he could become the finest pianist in Europe, but a hand injury ended this dream. Schumann then focused his musical energies on composing.
Schumann's published compositions were written exclusively for the piano until 1840; he later composed works for piano and orchestra; many Lieder (songs for voice and piano); four symphonies; an opera; and other orchestral, choral, and chamber works. Works such as Carnaval, Symphonic Studies, Kinderszenen, Kreisleriana, and the Fantasie in C are among his most famous. His writings about music appeared mostly in the Neue Zeitschrift für Musik (New Journal for Music), a Leipzig-based publication which he jointly founded.
In 1840, Schumann married Friedrich Wieck's daughter Clara, against the wishes of her father, following a long and acrimonious legal battle, which found in favour of Clara and Robert. Clara also composed music and had a considerable concert career as a pianist, the earnings from which, before her marriage, formed a substantial part of her father's fortune.
Schumann suffered from a mental disorder, first manifesting itself in 1833 as a severe melancholic depressive episode, which recurred several times alternating with phases of ‘exaltation’ and increasingly also delusional ideas of being poisoned or threatened with metallic items. After a suicide attempt in 1854, Schumann was admitted to a mental asylum, at his own request, in Endenich near Bonn. Diagnosed with "psychotic melancholia", Schumann died two years later in 1856 without having recovered from his mental illness.

Clara Wieck was a pupil of her father Friedrich in Frankfurt and performed for the first time in public when she was ten years old, with success. After a lot of squabbles, she married Robert Schumann in 1840, and she was a close friend of Brahms, especially after Schumann's death in 1856. She worked as a piano teacher, first in Berlin and later in Frankfurt, from 1878-1892.
As a pianist of European stature she made since 1832 concert tours to Russia, the Netherlands and England. She mainly excelled in the work of Beethoven, Schumann and Chopin, and later on Brahms.
As a composer, she wrote a piano concerto, chamber music, a piano sonata, short piano pieces, songs and cadences for piano concertos by Mozart and Beethoven.
(Source: Musicalifeiten.nl)