Piano keyboards have not always been the size they are today; between 1784 and 1876, they had narrower keys. Sakai (2008) has documented the variations in keyboard span of various keyboard instruments dating back to 1559. See: http://www.steinbuhler.com/html/our_research.html . These range from 180 mm for the clavichord to 188 mm (measured across eight keys) for the modern piano keyboard. Much of the best known piano repertoire was written between 1750 and 1850 at a time when the keyboard was smaller (with narrower keys) and repertoire rarely contained intervals larger than an octave.
In the nineteenth century, European composers such as Liszt had strong links with the major manufacturers who organised tours for these composers/virtuosos in order to market their products. They even built and managed concert halls. For example, Anton Rubinstein and Paderewski both toured the US for Steinway in the late 1800s.
Like cooking and sewing, piano playing was seen as highly desirable accomplishment for middle and upper class women. For them, the piano was an integral part of domestic activity, including the courting ritual. There was a clear distinction between amateurs (mostly women) who performed in the home and public performers (mostly men). In the 1800s, separate competitions were held for men and women in the Paris Conservatoire. Women were expected to be dignified, feminine and graceful, and were warned by Karl Czerny and others not to play certain types of repertoire. Direct comparisons with men were not welcomed. A Czech company did market a smaller keyboard for ‘ladies’.