Alsa
Alsa a small river of Venetia (Plin. Nat. 3.18. s.22) still called the Ausa, which flows into the lagunes of Marano, a few miles W. of Aquileia. A battle was fought on its banks in A.D. 340, between the younger Constantine and the generals of his brother Constans, in which Constantine himself was slain, and his body thrown into the river Alsa. (Victor, Epit. 41.21; Hieron. Chron. ad ann. 2356.)
From William Smith (ed.), Dictionary of Greek and Roman Geography. Text provided under a CC BY-SA license by Perseus Digital Library, http://www.perseus.tufts.edu, with funding from the National Endowment for the Humanities and Tufts University. Data accessed from https://github.com/PerseusDL/canonical-pdlrefwk/ on 17 October 2026.