Elizabeth of Bosnia (Serbo-Croatian: Elizabeta Kotromanić/Јелисавета Котроманић; Hungarian: Kotromanics Erzsébet; Polish: Elżbieta Bośniaczka; c. 1339 – January 1387) was queen consort of Hungary and Croatia, and queen consort of Poland, and, after becoming widowed, the regent of Hungary and Croatia between 1382 and 1385 and in 1386.
Daughter of Ban Stephen II of Bosnia, Elizabeth became Queen of Hungary upon marrying King Louis I the Great in 1353. In 1370, she gave birth to a long-anticipated heir, Catherine, and became Queen of Poland when Louis ascended the Polish throne. The royal couple had two more daughters, Mary and Hedwig, but Catherine died in 1378. Initially a consort with no substantial influence, Elizabeth then started surrounding herself with noblemen loyal to her, led by her favourite, Nicholas I Garai. When Louis died in 1382, Mary succeeded him with Elizabeth as regent. Unable to preserve the personal union of Hungary and Poland, Elizabeth secured the Polish throne for her youngest daughter, Hedwig.