who lived in what is now those countries were largely homogeneous and similar in culture and language, although somewhat distinct geographically. The names of Scandinavian kings are reliably known for only the later part of the Viking Age. After the end of the Viking Age the separate kingdoms gradually acquired distinct identities as nations, which went hand-in-hand with their Christianisation. Thus the end of the Viking Age for the Scandinavians also marks the start of their relatively brief Middle Ages. Intermixing with the Slavs Slavic and Viking tribes were "closely linked, fighting one another, intermixing and trading". In the Middle Ages, goods were transferred from Slavic areas to Scandinavia, and Denmark could be considered "a melting pot of Slavic and Scandinavian elements". Leszek Gardeła, of the Department of Scandinavian Languages and Literatures at the University of Bonn, posits that the presence of Slavs in Scandinavia is "more significant than previously thought", while Mats Roslund states that "the Slavs and their interaction with Scandinavia have not been adequately investigated". A 10th-century grave of a warrior-woman in Denmark was long thought to belong to a Viking. However, new analyses suggest that the woman may have been a Slav from present-day Poland. The first king of the Swedes, Eric, was married to Gunhild, of the Polish House of Piast. Likewise, his son, Olof, fell in love with Edla, a Slavic woman, and took her as his frilla (concubine). They had a son and a daughter: Emund the Old, King of Sweden, and Astrid, Queen of Norway. Cnut the Great, King of Denmark, England and Norway, was the son of a daughter of Mieszko I of Poland, possibly the former Polish queen of Sweden, wife of Eric. Richeza of Poland, Queen of Sweden, married Magnus the Strong, and they had several children, including Canute V, King of Denmark. Catherine Jagiellon, of the House of Jagiellon, was married to John III, King of Sweden. She was the mother of Sigismund III Vasa, King of Poland, King of Sweden, and Grand Duke of Finland. Ragnvald Ulfsson, son of Jarl Ulf Tostesson and the Wendic Princess Ingeborg, had a Slavic name (Rogvolod, from ). Expansion Colonisation of Iceland by Norwegian Vikings began in the 9th century. The first source mentioning Iceland and Greenland is a papal letter of 1053. Twenty years later, they appear in the Gesta of Adam of Bremen. It was not until after 1130,