 Harald took part in Yaroslav's campaign against the Poles in 1031, and possibly also fought against other 1030s Kievan enemies and rivals such as the Chudes in Estonia, the Byzantines, as well as the Pechenegs and other steppe nomad people.After a few years in Kievan Rus', Harald and his force of around 500 men moved on south to Constantinople ("Miklagard"), the capital of the Eastern Roman Empire (later known as the Byzantine Empire), probably in 1033 or 1034, where they joined the Varangian Guard.Although the "Flateyjarbók" maintains that Harald at first sought to keep his royal identity a secret, most sources agree that Harald and his men's reputation was well known in the east at the time.