1580s, "besiege, surround, blockade," literal and figurative, from Dutch or Low German belegeren "to besiege," from be- "around" (from Proto-Germanic *bi- "around, about;" see by) + legeren "to camp," from leger "bed, camp, army, lair," from Proto-Germanic *legraz-, from PIE *legh-ro-, suffixed form of root *legh- "to lie down, lay." A word from the Flemish Wars (cognates: Swedish belägra, Dutch belegeren "besiege," German Belagerung "siege"). Spelling influenced by league. Related: Beleaguered; beleaguering.