Rabbi Shlomo Ganzfried and his most famous book, Kitzur Shulhan Aruch, had a long-lasting impact on the Orthodox Jewish world. The Kitzur is one of the most popular Jewish books of all time, and until the middle of the 20th century one of the most influential.
Rav Ganzfried lived in Hungary at a time of upheaval – the Austro-Hungarian Compromise of 1867 followed by (even more significantly for the Hungarian Jewish world) the Congress of 1869. He strongly opposed the nascent Neolog movement, and wrote strongly against teaching secular knowledge in yeshivot.
