Which composer is recognized for writing some of the first keyboard music?

The composer recognized for writing some of the first keyboard music is William Byrd. Byrd was an English composer active during the late Renaissance period, and he notably contributed to the development of keyboard music, particularly through his collections of keyboard pieces, such as the "Psalms, Sonnets and Songs" and "My Ladye Nevells Booke," which included a variety of compositions specifically for the virginal and harpsichord.

His works reflect both the evolving style of the period and the increasing importance of keyboard instruments in musical practices. Byrd's music paved the way for future developments in keyboard composition, influencing subsequent composers and the repertoire for keyboard instruments.

The other composers listed, while significant in their own right and periods, did not primarily focus on keyboard music in the same foundational way that Byrd did. For example, John Dowland is most known for his vocal music and lute songs. Henry Purcell, although he composed for keyboard occasionally, is celebrated primarily for his vocal compositions, particularly in the realm of opera and sacred music. George Frideric Handel's contributions were predominantly in the areas of opera, oratorio, and orchestral music, with his keyboard works being less representative of the early keyboard repertoire compared to Byrd’s