A reliable seismic hazard assessment is of great importance in engineering projects. Poland is a country of low seismic activity, and historical seismological documentation is scanty and difficult to retrieve. This book re-examines and provides new data retrieved for some of the 18th and 19th century earthquakes that either occurred or were clearly felt in southern regions of Poland. Particular emphasis is put on a detailed study and reinterpretation of the unusually strong and deep Outer Western Carpathians earthquake on December 3, 1786 (7 I0, 5.3 Mw, 35 km depth), which completed a series of seismic events in the years 1785 and 1786. An assessment is also made of what we presently know about the seismicity of the Western Carpathians in Poland according to instrumental data.Further materials are related to earthquakes of 6-9 I0 that affected south Poland and surrounding regions: ?ilina in Slovakia (1858), Gera in Thuringia (1872), the Sudetes on the Czech-Polish border (1883, 1901), and Lower Silesia, Poland (1895), which are analyzed and illustrated by 17 contemporary macroseismic intensity maps, some of them considered as remarkable macroseismic maps of those times.Another important contribution is a new seismic catalog for Poland, amended and updated until the end of 2014. Noteworthy are data on the two unexpected events: about 60 km NE of the Polish border in 2004 and the one in central Poland in 2012. This shows how important it is, also for practical engineering purposes, to make seismic monitoring even in seemingly aseismic regions.