The Vikings were the Norse warriors, explorers and merchants who raided, explored and settled wide areas of England, Scotland, Ireland, Wales, Iceland, France, Spain, Africa, and Italy. They started their expansion by executing multiple raids of the English shores. According to the Anglo-Saxon Chronicles, Viking raiders struck England in 793 AD and raided Lindisfarne, the monastery that held Saint Cuthbert’s relics. Their raids continued to increase in frequency and the number of participating troops, until in 865 AD the Great Heathen Army led by the Brothers Ivar the Boneless, Halfdan and Ubbe Ragnarsson arrived in East Anglia and established their presence in the Northern England until they were driven out by the English king Harold Godwinson in 1066. The archeologists and linguists recently came to a conclusion that all British towns that end with "by" - for example, Ashby, Corby, Crosby, etc. - were founded and named by the Viking invaders.
Interestingly enough Harold lost the famous Battle of Hastings in the same year to another descendant of the Vikings (Normans) who settled in the Northern France a hundred or so years prior to the events, future king William the Conqueror (or William the Bastard as he was known before the battle).
According to the Russian "Primary Chronicle" three Viking - or Varangian as they were known in Russia - brothers Rurik, Truvor and Sineus were the first kings of the Russian royal dynasty that spanned from the 9th until the 16th century. And, yes, famous (or infamous) Russian tsar, Ivan the Terrible who was a last ruling member of the Rurikid dynasty can trace his roots directly to the Swedish warriors, who arrived in Russia almost seven centuries prior to his birth.
After establishing their foothold in Russia, many of the Vikings travelled South to the Caspian Sea and farther to the Byzantium Empire, where many of the enlisted in the much-feared Varangian Guard of the Byzantine Emperors.
In the XXI century a branch of the Norman royal family headed by the Roger I conquered Sicily and ruled there for the next two hundred years. Vikings also reached the shores of North America where Erik Thorvaldsson and his son Leif Ericson established several colonies in what is today known as Newfoundland.