Unno was a duke from the medieval Frisian shire of Rüstringen. In the Frankish annals, Unno is described as a Frisian duke. He belonged to the Frisian elite who were willing to cooperate with the Franks after annexation of East Frisia in 772. In exchange for retaining their old privileges they had to become Christian and leave their pagan beliefs...
'cloud robe' = unsui