Complex sentence: On his return to Spain in 1892, he was appointed to the command first of the 6th Army Corps in the Basque Provinces and Navarre, where he soon quelled agitations, and then as captain-general at Barcelona, where he remained until January 1896.
Split into simpler sentences: On his return to Spain in 1892, he was appointed to command the 6th Army Corps in the Basque Provinces and Navarre, where he soon quelled agitations. He was then made captain-general at Barcelona, where he remained until January 1896.