​MURPHYSBORO, a city and the county-seat of Jackson county, Illinois, U.S.A, in the south part of the state, on the Big Muddy River, about 57 m. N. of Cairo. Pop. (1890), 3880; (1900), 6463, including 557 foreign-born and 456 negroes; (1910), 7485. It is served by the Illinois Central, the Mobile & Ohio and the St Louis, Iron Mountain & Southern railways. It is the centre for a farming region, in which there are deposits of coal, iron, lead and shale, and there are various manufactures in the city. Murphysboro was incorporated in 1867, and reincorporated in 1875.