Władysław I the Elbow-high of Kujawy, however, as he had two older half-brothers from Casimir’s second marriage to Constance of Wrocław: Leszek II the Black ("Leszek Czarny") and Ziemomysł. He was named after his uncle, his mother's brother Władysław, Duke of Opole. Already in contemporary sources he was nicknamed ""Łokietek"", a diminutive of the word "łokieć". It translates as "elbow" or "ell" – a medieval unit of measure similar to a cubit, as in "elbow-high". The origin of this nickname, as resulting from Władysław’s short stature, was explained only in the 15th century by historian Jan Dlugosz. In 1267, when Władysław the Elbow-high was
Ancient Mesopotamian units of measurement construct the calendar were the synodic month, equinox year, and sidereal day. The Classical Mesopotamian system formed the basis for Elamite, Hebrew, Urartian, Hurrian, Hittite, Ugaritic, Phoenician, Babylonian, Assyrian, Persian, Arabic, and Islamic metrologies. The Classical Mesopotamian System also has a proportional relationship, by virtue of standardized commerce, to Bronze Age Harappan and Egyptian metrologies. Ancient Mesopotamian units of measurement Ancient Mesopotamian units of measurement originated in the loosely organized city-states of Early Dynastic Sumer. Each city, kingdom and trade guild had its own standards until the formation of the Akkadian Empire when Sargon of Akkad issued a common standard.