The name Lötz comes from a man who apparently had very little to do with glass, Johann Lötz. Some time after he died in 1844, his wife Suzanna remarried, to Dr. Franz Gerstner. In 1851, the bought the Klastersky Mlyn glassworks, which was originally founded in 1836 by Johann Baptist Eisner von Eisenstein, in the town of Klostermuhle, south Bohemia. The name of the factory was changed to Johann Lötz Witwe, which means "the widow of Johann Lötz". This was shortened to Lötz, and around the turn of the century was anglicized to Loetz.
Susanna's grandson Max Ritter von Spaun took over the company in 1879, and a year later hired Eduard Prochaska as director. Production moved from domestic utility glass to luxury glass, and in 1895, inspired by Tiffany, Loetz began to make Art Nouveau style glassware with an iridescent lustre finish, for which Loetz is so well known today. The Loetz glassworks closed in 1947.
Sources: 20th Century Factory Glass by Lesley Jackson.