Modern scholarship does not see sagas such as the "Ynglinga saga" as good sources for genuine historical information. As a historical source, the "Ynglinga saga" is much better used as a source on historiography and society during Sturluson's own time than as a source on Sweden's early history. It is possible that the Yngling line of kings is entirely fictional, invented by later Norwegian rulers to assert their right to rule Norway. In the Viking Age and later, Danish rulers repeatedly attempted to conquer Norway and through inventing a lineage that stretched back centuries, the Norwegian rulers may have attempted to demonstrate their inherent right to their lands and to put themselves on the same level as the Danes, who had historical accounts of their ancestors. The Swedish Ynglings might have been invented to glorify the Norwegian kings further, giving them a glorious and mythical past associated with Uppsala. Most of the sagas known today, the "Ynglinga saga" included, were composed during a relatively brief period, from the 12th to 13th century, a time when royal power was being consolidated in Norway, Denmark and Sweden. Their creation might thus stem from political and social needs (i. e. justifying the rule of a dynasty), rather than a desire to tell genuine history. In addition to having been written centuries after the events they describe, the sagas have numerous other problems which make them unsuitable to use as sources. Many of the elements of the "Ynglinga saga" appear to be based on later, documented, events and people in Scandinavia. For instance, the figure of Aun, described as being driven from Uppsala and taking up court in Västergötland instead, is similar to the historical Swedish king Inge the Elder ( 1079–1084, 1087–1105), who was driven from Uppsala into Västergötland in the 11th century. The "Ynglinga saga" might also be an example of anti-royal social commentary rather than an attempt to tell history. Many of the kings in the saga are overshadowed by their contemporary vassals and wives, and they are rarely shown in a positive light. The inglorious deaths of many of the Swedish Ynglings; with examples such as murder, burning to death, drowning in mead and being "hag-ridden" to death, might be an attempt by Sturluson to say that the kings who ruled Norway in his time and claimed Yngling descent were not to be taken seriously.