No historical records or lists of Anglo-Saxons of this period mention a king "Houad". However, with Northumbria suffering from repeated incursions from the Picts, Scots and Danes, "Hoaud" may have been a local warlord or a Danish freebooter carving out his own domain in Northumbria.
Anglo-Saxon. Kings of Northumbria. Hoaud. Ca 850. BI Styca (1.02 gm, 7h). Moneyer: Huaetred. +HOAVD RE around central cross / +HVAETRD around central cross. Pirie 451 (same dies); Axe, "Dating the so-called Hoaud stycas," BAR 180, pl. 22, 1 (same dies).