On 4 April 1253, in a treaty drawn up at Kuldīga between Bishop Heinrich of Courland and the Teutonic Order concerning the division of conquered Curonian lands, Lyva appears – the Līva village from which Liepāja grew. In the document, Lyva is mentioned together with the lake as a shared and free place where no one could act without permission. For this reason, 4 April is one of the earliest precisely datable days in Liepāja’s written history.

In the mid-13th century, Courland was being drawn into the world of the crusades and Livonian power structures. Such land-division documents often became the first written record of local settlements, and the name Līva later became part of Liepāja’s historical identity.