The origin of printed sheet music dates to 1476 and Roman printer Ulrich Hans. However the father of modern music printing is generally acknowledged to be Ottaviano Pettruci, a Venetian Printer and publisher active in the early decades of the 16th Century. The next significant development in publishing was the creating of copyright law with its origins in England at the time of Henry VIII. It granted printers legal protections in the form of licenses and it was further modified under the Statute of Anne 1710.
Germany was the pioneer in modern music publishing. The first German music publishing enterprises date from the 18th century. Bernhard Christoph Breitkopf of Leipzig, a printer and general publisher, decided to specialize in music printing as of 1754. He became successful by developing improvements in the setting of music type. Gottfried Christoph Härtel joined the firm in 1795, which soon became the partnership of Breitkopf & Härtel. They were the original publishers for a who’s-who of great German composers, including Beethoven, Haydn, Mozart, Schubert, Schumann and Wagner.
Schott Music of Mainz was founded in 1770 by Bernhard Schott and still exists today. They specialized in French and Italian operas N. Simrock of Bonn, and later Berlin, was established in 1790 by Nikolaus Simrock. Their original publications included works by Beethoven, Haydn, Meyerbeer, Weber, Mendelssohn, Schumann and Brahms.
The development of music publishing goes hand with the developments in printing the written word. To show how one house carried on this is taken from wikipedia
The Schott publishing house was founded by Bernhard Schott (1748–1809) in Mainz in 1770, the year of Beethoven’s birth. The building, dated and now under a preservation order, is still the company’s head office. At the time of the foundation of the publishing house, Mainz boasted a flourishing cultural life and a busy court chapel. In 1780, Bernhard Schott was awarded the ‘privilegium exclusivum’ together with the title of ‘Court music engraver’. This meant that within the boundaries of the electorate of Mainz no third party was allowed to re-engrave or sell the works produced by him. Schott was one of the first publishers to use the printing technique of lithography, which meant that his editions were soon being printed and distributed on a wide scale.
During the French years of Mainz, the publisher suffered from high taxes, but the affectation to French music helped him in this stage. As a later consequence, the publishing house rapidly became established beyond the national borders of Germany. As early as 1823, Schott founded a branch in Antwerp, relocated to Brussels in 1839 (called Schott frères from 1879 onwards), and further offices in musical centres such as Leipzig, London, Paris and Vienna. From the very beginning, it was its commitment to contemporary music that earned the publishing house its international reputation. Initially, the publishing programme included works by composers from the Mannheim School such as Carl Stamitz and Georg Joseph Vogler, as well as virtuoso ballroom music and comic operas. The publication of the piano scores and first editions of Mozart’s opera Don Giovanni and Die Entführung aus dem Serail were among the highlights of the publishing house’s early history. They were soon followed by major late works of Ludwig van Beethoven, including the Ninth Symphony, the Missa Solemnis and the last two string quartets.
I believe that the increasing availability of published music affected the European Scene in many ways. If a composer could get his music published then he would have a source of income and do away with the need for patrons. Patronage was diminishing but there were still wealthy people who would patronise musicians. The widespread availability of music made it easier for the public to have their favourite music at their hand and this in turn led to music being played more at home and the demand for pianos increased. You could extend this and bring in the subject of royalties from performance of these works.