Saxonburg is a borough in Butler County, Pennsylvania, United States. It is part of the Greater Pittsburgh area in Western Pennsylvania. It was founded in 1832 by F. Carl Roebling and his younger brother John as a German farming colony. The population of Saxonburg was 1,525 as of the 2010 census. The city was first named "Germania" and "Sachsenburg" before its name was Anglicized to the present one.