King's County, a county of Ireland in the province of Leinster, bounded by Co. Westmeath on the N., Roscommon on the N.W., Galway on the W., Tipperary on the S.W., Kildare on the E., and Queen's County on the S.; area, 772 square miles. The surface is level, comprising a large portion of the Bog of Allen, besides numerous other bogs; but on the S. border there is a mountainous district, consisting of the western half of the Slieve Bloom range. The soil, chiefly a gravelly loam, is fairly good. The Shannon skirts the N.W. border. The county was formed in 1557, and named after Philip of Spain.