Isaac Ignaz Moscheles (German pronunciation: [ˈɪɡnaːts ˈmɔʃələs]; 23 May 1794[1] – 10 March 1870) was a Bohemian piano virtuoso and composer.

He was based initially in London and later at Leipzig, where he joined his friend and sometime pupil Felix Mendelssohn as professor of piano in the Conservatory.

Ignaz developed an early passion for the (then revolutionary) piano music of Beethoven, which the Mozartean Bedřich Diviš Weber, his teacher at the Prague Conservatory, attempted to curb, urging him to focus on Bach, Mozart and Muzio Clementi.

Here, too, he became a close friend of Giacomo Meyerbeer, at that time still a piano virtuoso, not yet a composer; their extemporized piano-duets were highly acclaimed.

[5] While in Vienna, Moscheles was able to meet his idol Beethoven, who was so impressed with the young man's abilities that he entrusted him with the preparation of the piano score of his opera Fidelio, commissioned by his publisher Artaria.

At the end of his manuscript, before presenting it to Beethoven, Moscheles wrote the words Fine mit gottes Hülfe ("Finished with God's help").

Beethoven approved Moscheles's version, but appended the words O Mensch, hilf dir selber ("O Man, help thyself!").

They were parents to the painters Felix (1833–1917), their second son, and Serena Anna Moscheles (1830–1902), their second daughter and wife of Georg Rosen.

[10][11] Moscheles travelled extensively in Europe as a pianist and conductor, eventually settling in London (1825–1846) where his address was 3, Chester Place, near Regent's Park.

Moscheles visited most of the great capitals of Europe, making his first appearance in London in 1822, and there securing the friendship of Muzio Clementi and Johann Baptist Cramer.

In March 1823, Moscheles paid a long visit to Bath in Somerset and started work on his Piano Concerto No.

[14] Before that, however, in 1824, he had accepted an invitation to visit Abraham Mendelssohn Bartholdy in Berlin to give some lessons to his children Felix and Fanny.

[12] Child prodigy pianist Elizabeth Jonas, a student of Moscheles, played several command performances at Windsor Castle.

He also often performed in concert with Mendelssohn in London (and elsewhere) – one great favourite of both musicians were Bach's concerti for multiple keyboard instruments.

[20] Although throughout this period Moscheles continued to write music and travel on concert tours, he depended heavily on teaching for income, and this placed him under considerable stress.

When therefore Mendelssohn established a Conservatory at Leipzig in 1843 he was keen to attract his friend Moscheles there as a colleague, promising him ample time in his schedules for concertising and music-making.

The critic and pianist Edward Dannreuther, who studied under Moscheles at Leipzig between 1859 and 1863, later wrote: [...] it was whispered that the two old Grands in the pianoforte-room of the Conservatorium were wont to rehearse Mendelssohn's D minor Concerto all alone by themselves, from 12.30 on Sunday night until cock-crow!

[22] Like Mendelssohn, Moscheles believed that music had reached its Golden Age during the period Bach to Beethoven, and was suspicious of (although not necessarily antagonistic towards) new directions such as those shown by Wagner, Liszt and Berlioz.

The Mendelssohn legacy in Britain meant that the Leipzig Conservatory had a high reputation amongst English musicians and amongst those who studied there during Moscheles's time were Arthur Sullivan and Charles Villiers Stanford.

[24] More recently, with the modest but noticeable revival of interest in compositions by this composer and those of his colleagues, more of Moscheles's works are being made accessible on compact disc, especially by small and independent record labels.

Much of what is known about Moscheles's life is derived from the biography, with selections from his diaries and correspondence, written after his death by his wife, Charlotte, and published in Germany in 1872; an English edition appeared the following year.