Leopold Jansa (born November 18, 1795, in Prague – died January 14, 1875, in Vienna) was a prominent Czech violinist, composer, and conductor primarily associated with the Romantic era of classical music. He was known for his virtuosic violin performances and significant contributions to the development of violin technique. Jansa's repertoire included a variety of compositions, but he is particularly noted for his concertos and chamber music, which showcased his skill as both a performer and composer. His notable works include several violin concertos and sonatas, which were well-received during his lifetime. Jansa had a substantial impact on music education, influencing future generations of violinists through his teaching in Vienna and his advocacy for the violin as a concert instrument. He was a contemporary of other notable musicians of his time and contributed to the rich tapestry of 19th-century music, helping to elevate the status of the violin in orchestral and solo performances. While he may not be as widely recognized today, his contributions to violin performance and pedagogy laid the groundwork for future developments in classical music.