The String Quartet No. 1 in F major, Op. 18, No. 1, was written by Ludwig van Beethoven between 1798 and 1800 and published in 1801. It is actually the second string quartet that Beethoven composed. According to Beethoven's friend Karl Amenda, the second movement was inspired by the tomb scene from William Shakespeare's Romeo and Juliet. The quartet was heavily revised between the version that Amenda first received and the version that was sent to the publisher a year later, including changing the second movement's marking from 'Adagio molto' to the more specific 'Adagio affetuouso ed appassionato'. The theme of the finale is almost directly borrowed from the finale of his earlier string trio, Op. 9, No. 3 in C minor; the themes are very closely related.